thiet ke phan xuong san xuat axit axetic 1733
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thiết kếTRANSCRIPT
DO AN TOT NGHIEP
n tt nghip Thit k phn xng sn xut axit axetic
1M u
3Phn I Tng quan
3Chng I Gii thiu chung v Axit axetic
3I.Tnh cht vt l
8II.Tnh cht ho hc ca Axit axetic
9II.1.Tnh axit
9II.2.Phn ng xy ra nguyn t cacbon ca nhm cacboxyl
9II.3.Phn ng Decacboxyl ho
10II.4.Phn ng to amit
10II.5.Phn ng loi nc to anhydrit
10II.6. Sau y l mt s phn ng quan trng ca axit axetic c s dng trong thc t
11III.ng dng
11III.1.Mui
12III.2.Este
12III.3.Axetyl clorua
12III.4.Amit
12III.5.Axit phenylaxetic
13III.6.Bng ng dng ca axit axetic
14Chng II Gii thiu chung v Nguyn liu Axetaldehyt
15I.Tnh cht vt l
17II. Tnh cht ho hc
17II.1.Phn ng cng hp
18II.2.Phn ng oxy ho, kh
18II.3.Phn ng phn hu
18II.4.Phn ng ngng t
18II.5.Mt s phn ng khc
20Chng III Cc phng php sn xut Axit axetic
20I.Qu trnh cacbonyl ho metanol
20I.1. Gii thiu
21I.2. Xc tc
21I.3.Bn cht ho hc v iu kin phn ng
25I.4. S cng ngh
25a. S cng ngh ca hng BASF
28b. S cng ngh ca hng Monsanto
30I.5.nh gi phng php ca BASF v Monsanto
30II.Qu trnh oxy ho trc tip hydrocacbon
30II.1. Oxy ho trc tip cc hydrocacbon no
38II.2. Oxy ho trc tip cc hydrocacbon khng no
43III. Phng php sn xut axit axetic t axetaldehyt
44III.1.Bn cht v iu kin phn ng
48IV.Qu trnh sn xut Axit axetic bng phng php oxy ho axetaldehyt trong pha lng.
48IV.1. C ch phn ng
49IV.2.Xc tc
51IV.3. Cc yu t nh hng n qu trnh
54V.Phng php vi sinh
54VI. Phng php ho hc g
55VII. Cc phng php tng hp khc
55VIII. So snh cc phng php sn xut axit axetic
56IX. Nng cao nng v tinh ch Axit axetic
56IX.1.Nng cao nng v tinh ch axit axetic
58IX.2.Cht lng sn phm
59Chng IV: cng ngh SN XUT AXIT AXETIC BNG PHNG PHP OXY HO AXETALDEHYT TRONG PHA LNG C XC TC
59I.Giai on oxy ho axetaldehyt
60II.Giai on tinh ct sn phm th
60III.Giai on lm sch axit axetic
60IV. Dy chuyn sn sut axit axetic t axetaldehyt
61V.Thit b oxy ho axetaldehyt
62I.Cc s liu ban u.
62iI.Tnh ton cho thit b oxy ho
62II.1.Cn bng vt cht
68II.2.Cn bng nhit lng
77IIi.tnh ton cho thit b tch phn nh
77III.1.Cn bng vt cht
79III.2.Cn bng nhit lng
82IV.Tnh ton cho thit b tch phn nng
82IV.1.Cn bng vt cht
83IV.2.Cn bng nhit lng
85V.tnh ton thit b oxy ho
85V.1.ng knh thit b
86V.2.Tnh chiu dy ca thit b
89V.3.Chn np v y thp
93V.4.Chn bch ni
94V.5. Chn cc ng knh ng dn vo v ra thit b chnh
95Phn III Tnh ton kinh t
95I. ngha
95II. Ni dung tnh ton kinh t
95II.1. Nhu cu v nguyn liu, nhin liu v nng lng.
95II.1.1.Nhu cu v nguyn liu.
96II.1.2.Nhu cu v in nng
98II.2. Tnh vn u t c nh.
98II.2.1. Vn u t xy dng
98II.2.2. Vn u t cho thit b, my mc
98II.3. Chi ph cho nhn cng lao ng
98II.3.1.Nhu cu v lao ng.
99II.3.2. Qu lng cng nhn vin trong phn xng.
100II.4.Tnh khu hao
100II.5.Tnh gi thnh sn phm
101II.6. Tng li nhun c nm.
101II.7. Thi gian thu hi vn
102Phn iv Thit k xy dng
102I.c s Chn a im xy dng
103II.Thit k xy dng tng mt bng nh my
108I.an ton lao ng
111II.t ng ha trong phn xng
119Kt lun
120Ti liu tham kho
LI CM N Sau mt thi gian lm n ,c s gip ca cc thy c gio trong b mn Cng ngh hu c _Ha du,c bit l thy gio hng dn GS.TS o Vn Tng ngi hng dn,gip em v mt kin thc khoa hc.Vi s gip tn tnh v n cn ca thy em hiu bit thm nhiu kin thc b ch v hon thnh bn n ng thi gian quy nh. Mt ln na,em xin chn thnh cm n thy GS.TS o Vn Tng cng ton th cc thy c gio,cc anh ch trong B mn Cng ngh hu c _Ho du v bn b to iu kin tt nht gip em hon thnh bn n ny.
H Ni ngy 27 thng 5 nm 2008 Sinh vin Hong nh Thi
M u
Axit axetic hay cn gi l axit etanoic, l mt hp cht hu c in hnh ca dy ng ng axit mono cacboxylic, n c nhiu ng dng trong sn xut v i sng, l mt trong nhng sn phm hu c c bn v quan trng c s dng rng ri trong cng ngh tng hp hu c ha du.
Axit axetic c s dng sn xut anhydric axetic, mui axetat, axit cloaxetic, hp cht nha, dc phm, thuc nhum v thuc tr su, ha cht ngnh nh, thc phm v ph gia cho thc phm (v d nh dm n, nc dm hoa qu, nc st), ngoi ra n c dng iu ch nhiu loi hp cht hu c khc. Axit axetic c s dng nhiu nht l sn xut vinyl axetat (VA). Vinyl axetat c nhiu ng dng trong ngnh dt, sn v giy.Trn Th gii, nhu cu s dng axit axetic d bo s tng t 3 - 4%/nm. M th nhu cu s dng axit axetic ch tng 1%/nm, nm 2005 l 2,52 triu tn v d kin n nm 2009 l 2,55 triu tn. Mc d, nm 2005 nc M xut khu 926000 tn axit axetic tng ng vi gn 37% nhu cu s dng trong nc [14].
Chu c tnh nhu cu s dng axit axetic s tng cao hn nhiu vo khong t 5 - 7%/nm, trong Trung Quc tng t 8 - 10%/nm. Theo BP, trong vng 5 nm qua nhu cu s dng axit axetic Trung Quc tng 15 - 16%/nm. Cng ty ha du Daqing ang xy dng nh my vi nng sut 200000 tn/nm v hon thin trong nm 2008. Cng ty ha du Yangzi vi i tc l BP cng ang xy dng nh my Nanjing vi nng sut 500000 tn/nm v s hon thin vo nm 2009. Trong tng lai, n cng l mt nc c nhu cu s dng axit axetic rt ln. Theo BP, n h thch si t nhin hn nn si polyeste c s dng rt t. Nhng iu ny s thay i khi m cng ngh sn xut polyeste c ci tin, v hy vng vic s dng VA cng s pht trin mnh n .
Trung ng, nm 2006 Cng ty ha du Fanavaran ca Iran xy dng nh my sn xut axit axetic vi nng sut 150000 tn/nm; v Cng ty ha du Saudi International hon thnh xong d n xy dng nh my sn xut axit axetic vi nng sut 460000 tn/nm s khi cng vo nm 2009. [14]
Cng nh cc nc trn Th gii, nhu cu s dng axit axetic Vit nam ngy cng cao. Hng nm chng ta phi nhp khu mt lng axit axetic kh ln. Qu trnh sn xut axit axetic trong nc ch yu bng phng php vi sinh cho nng axit thp, nng sut khng cao nn cha p ng c nhu cu. T nhng nm 1990, mt s c quan nghin cu khoa hc nc ta nghin cu sn xut axit axetic cng nghip. Vin Ha hc Cng nghip cng nghin cu ti s dng ru etylic sn xut axit axetic. Mt s c quan nghin cu khoa hc khc nh Vin Ha hc thuc Trung tm Khoa hc T nhin v Cng ngh Quc gia, khoa Ha thuc trng i hc Tng hp H ni cng quan tm n ti ny [15]. Nhng do nhiu nguyn nhn m cc kt qu nghin cu vn cha c p dng trong sn xut cng nghip. Cho n nay, gn nh ton b nhu cu axit axetic nc ta u phi p ng bng con ng nhp khu.
Trc tnh hnh mi, c hi pht trin cho ngnh cng nghip ha cht c m ra, th qu trnh sn xut axit axetic c nng cao tr thnh mt vn quan trng v vic tm ra phng php sn xut axit axetic p ng c nhu cu s dng v c hiu qu kinh t l mt vic lm ht sc cn thit. Sn xut axit axetic trong cng nghip c rt nhiu phng php, nhng phng php quan trng v c ngha hn c l oxy ha axetaldehyd. Phng php ny cho sn phm axit axetic tinh khit c nng cao v hiu sut qu trnh ln.
Phn I Tng quan
Chng IGii thiu chung v Axit axetic
Con ngi bit n gim t rt lu vi mc ch lm gia v, l dung dch 4 ( 12% axit axetic c sn xut bng phng php ln men ru).
Axit axetic l mt axit hu c yu c cng thc phn t CH3COOH, khi lng phn t M = 60,05, l cht lng khng mu, c tnh n mn. Axit axetic c mi hng v l cht nguy him i vi da. Axit axetic c tm thy trong dung dch long trong rt nhiu h ng vt cng nh thc vt. Hin nay, cc nc sn xut axit axetic theo phng php tng hp nhiu nht l M, chu u, Nht, Canada, v Mexico. Tng cng sut ca cc nh my sn xut Axit axetic ti cc nc ny t khong 4 triu tn/nm. Axit axetic c nhiu ng dng quan trng, nhng dn xut ca Axit axetic c ng dng rng ri nht l vinyl axetat v anhydrit axetic. Vinyl axetat c s dng trong qu trnh sn xut sn, keo dn, giy bc, v trong cng nghip dt. Anhydrit axetic c s dng sn xut si xenlulo axetat, u lc thuc l v nha xenlulo, x l si.I.Tnh cht vt l
Axit axetic c nhit nng chy 16,66oC, nhit si 117,9oC p sut 101,3 kPa; l cht lng khng mu, trong sut. Axit axetic khng tinh khit thng ln cc tp cht nh nc, anhydrit axetic, v cc cht d oxy ho khc. Axit axetic bng(cha 99%) c tch ra vi hiu sut khong 60%. c bit i vi oxy ho naphta mt vi diaxit c thu hi lm thng phm, nhng cht d khng bay hi c t thu hi nng lng.
II.1.3. S dy chuyn sn xut
a. S oxi ho trc tip n-butan trong pha lng (LPO) : (hnh 3)
Hnh 3:S oxi ho trc tip n-butan trong pha lng (LPO)(Dy chuyn sn xut ca Werke Huls)
a. Thit b phn ng d. Thit b phn chia
b. Lm lnh bng khng kh e. Ct p sut
c. Collector f. Ct chng tch.
Thuyt minh dy chuyn sn xutThit b phn ng (a) c cha 1 ng phun nc cho l phn ng hoc nhiu ng phn tch tng pha tch kh v 2 pha lng c hnh thnh do dng ra khi thit b phn ng.
Tc nhn oxy ho c th dng l khng kh hoc a phn dng l khng kh giu oxy. Cc bnh phn ng c coi l ct hoc trong oxi ho naphta, gi l bnh phn ng hnh ng . Trong trng hp tng hp cc cht trung gian c bit l 2-butanol th c th b tr bnh phn ng thnh cc on v ly sn phm trung gian gia bnh phn ng.
Nhit qu trnh thng l 150-2000 C (nhit ti hn ca n- butan l 1520C) , p sut trong bnh duy tr mc 5,6 MPa . Hi nc c sinh ra t nhit ca phn ng. Dung mi ca phn ng gm c axit axetic, cc sn phm trung gian, nc v hydrocacbon ho tan. Kh khn nht l vic iu chnh hm lng nc c trong hn hp nm trong mt gii hn cho php v vn tch nc ra khi axt rt phc tp. Cc ion kim loi Mn, Co, Ni, Cr c s dng nh cht xc tc cho qu trnh.
Hi hydrocacbon trong kh t thit b phn ng (a) c thu hi v cho tun hon tr li. Ti y c s dng h thng tuabin gin n kh (b) tn dng cng tha ca kh nn khng kh trc khi a vo thit b phn ng.
Cc hp cht hu c t thit b phn chia pha (d) s c tun hon tr li thit b phn ng. Lp di l pha nc c chng tch v thu hi hydrocacbon.
Phn cn bao gm cc sn phm hydrocacbon quan trng nh dn xut ca cc cht oxi ho trung tnh (ch yu l anldehyt, xton, este v ru), nc, axit mono d bay hi (formic, axetic, propionic, butyric) v cc cht khng bay hi nh cn xc tc, cn sn phm, ...
Vic tch nc l rt kh khn do nc v axit axetic to thnh hn hp ng ph, do phi s dng n chng ct ng ph s dng tc nhn cun theo nh este hoc c th dng phng php chit.
b. Tng hp axit axetic bng oxi ho phn on nh ca xng: (hnh 4)
Hnh 4: S cng ngh oxy ho phn on nh ca xng.
1. Thp phn ng 4.Trao i nhit 7. Bm
2. Thp chng phn on 5. Lm ngui 8. Tch li
3. Thit b ti sinh hi 6. My gim p 9. Ni un
Phn on nh ca xng cha n-parafin v iso-parafin nn s lm cho tin trnh phn ng cng nh thnh phn ca sn phm rt phc tp.
Tuy vy, cc sn phm c th chia thnh 2 nhm axit (formic, axit axetic, propionic..) v cc hp cht trung gian (ru, axeton). Nhm sau cng thng d bay hi (to ra hn hp ng ph vi nc) v iu ny cho php tch cc cht trung gian ra khi axit v a chng tham gia tr li qu trnh oxi ho. T phn on axit s tch c cc axit formic, axit axetic, propionic, sucxinic : hiu sut ca chng tnh trn 100 kg xng tng ng l 20; 70-75 ; 10-15 v 5-10 kg.
S oxy ho xng tin hnh khng c xc tc hay c xc tc 170-2000C v 5 MPa . V rng cc sn phm chnh bn vi s oxi ho tip tc nn thit b phn ng thng l dng thp sc kh n gin trong nhit to ra s dng bay hi xng v cc sn phm trung gian ca s oxi ho . Hn hp phn ng s a qua thp (2) chng ct xng khng chuyn ho v cc cht trung gian a tr v thit b phn ng . Cht lng y thp ny s em tch cc axit .
Thnh cng ca qui trnh trn khng ch th hn s n gin ho giai on phn tch cc sn phm m cn lm tng hiu qu s dng nng lng ca h thng, khng kh d cng vi hi ca cc hu c pha trn thit b phn ng s cho qua thit b ti sinh hi (3), y ti sinh hi c p sut ph hp. Sau nhit ca kh c s dng trong phn trao i nhit (4) un nng nc, cn p sut kh trong b phn gim p (6) s thay i nh th m b phn lm ngui (5) t kh s ngng t c phn cn d ca hi xng. Phn ngng t ny s a tr li v thp (1) oxi ho.
II.2. Oxy ho trc tip cc hydrocacbon khng no
Axit axetic c th sn xut c t qu trnh oxy ho trc tip etylen, nhng qu trnh ny ch m t mt bc ca cng ngh sn xut v tinh ch axetaldehyt c nng sut ln trong thi gian va qua.
Vic sn xut axit axetic t popylen cng c pht trin , qu trnh ny xy ra trong pha kh vi s c mt ca xc tc oxit kim loi (U, W, Mo, Ti, ...) v hi nc nhit 250(4000C, p sut thng nhng hiu sut khng qu 50(70%.
Tuy nhin, olefin ch yu sn xut axit axetic trong cng nghip l n-buten. Qa trnh c tin hnh trc tip trong pha hi hoc pha lng, hoc gin tip qua hp cht trung gian l butyl axetat.
Oxy ho trc tip n-buten
Phng trnh phn ng xy ra nh sau:
n-C4H8 + 2O2 2CH3COOH , (H=-985 kj/mol
Qa trnh ny c th t c trong hn hp ca isome. Trong hn hp tn ti cn bng nhit ng gia 1-buten v 2-buten, chng c th b km hm hoc xy ra s bin i mau l hn. Sn phm trung gian ca qu trnh ny l axeton v axetaldehyt.
Qa trnh ny xy ra tt nht trong pha kh vi s c mt ca oxy d, chuyn ho t 60(90%, chn lc 50(70%. Qa trnh ny chu s nh hng ca hi nc v oxy, xy ra 250(3000C, p sut 1,5(3Mpa vi s c mt ca oxyt vanadi hoc cc xc tc baz khc nhau. Cc sn phm ph gm cc hp cht axit (formic, maleic, propyonic, acrylic...), aldehyt (formandehyt, axetaldehyt, ...), ancohol (isopropanol, butanol...), keton (axeton, metyl-etyl keton...), este, CO, CO2.
Qa trnh oxy ho trong cng nghip gm hai giai on chnh:
+ Giai on 1: Gia nhit nguyn liu n-buten n nhit cn thit v a vo thit b oxy ho bng khng kh trong lp xc tc lng, vi mc ch m b trao i nhit trong sut qu trnh chuyn ho bng sn phm hi. + Giai on 2: Tch sn phm v cc thnh phn phc tp khc sau khi phn ly kh thi nh cc qu trnh chng n gin v chng ng ph.
Cng ngh ca qu trnh ny c a ra bi hng Chemische Werke Huls. Tuy nhin cng ngh ny ch dng li nghin cu m cha a vo sn xut trong cng nghip. Oxy ho n-buten qua hp cht trung gian butyl axetat khc phc nhng hn ch ca qu trnh oxy ho trc tip n-buten, Bayer a ra cng ngh oxy ho vi qu trnh xy ra qua hp cht trung gian l butyl axetat.
Qa trnh sn xut axit axetic c tin hnh qua hai bc sau:
+ Este ho n-buten:
n-C4H8 + CH3COOH CH3-CH2-CH-O-C-CH3
+ Cracking hp cht trung gian:
CH3-CH2-CH-O-C-CH3 + 2O2 3CH3COOH
Qu trnh sn xut axit axetic gm 3 giai on sau: (S cng ngh c biu din trn hnh 5)
Este ho n- buten
Qu trnh c tin hnh trong thit b phn ng dng thng khuy 1100C v p sut 1,5 ( 2 Mpa. Ton b C4 c a vo cng vi axit axetic v 20% (trng lng) ca xc tc (ion trao i) trong butyl axetat. Hn hp ra c gi 1050C v 0,7 Mpa nhm tch ring butan v n-buten cha phn ng.Xc tc nh bm ly tm v tun hon tr li, chuyn ha ca n-buten t 50(80%. Cracking butyl axetatQu trnh cracking xy ra trong pha lng vi s c mt ca oxy hoc khgn kh 195 0C v 6 Mpa ,khng c xc tc trong thit b phn ng dng thng ng,
chuyn ha t 30( 50%,hiu sut qu trnh khong 80%.Kh cn li trong thit b phn ng c ra bng axit axetic trong dng chy ca xc tc (490 0C v 6 Mpa ) sau c tuc bin ca my nn y ra ngoi .
Tinh ch axit axeticBng qu trnh chng ng ph tch v tun hon butyl axetat cha phn ng v cc sn phm trung gian khc ca qu trnh .Sau l cc qu trnh tch axit formic ,axit axetic v tun hon tr li mt phn n qu trnh este ha.
Do hiu sut ca qu trnh rt thp (45(55%) nn qu trnh ny khgn cn c s dng trong cng nghip.
III. Phng php sn xut axit axetic t axetaldehyt
Phng php oxy ha axetaldehyt iu ch axit axetic c s dng rng ri trong cng nghip ,phn ng ca qu trng nh sau : +To thnh peroxit axetyl,sau phn hy thnh axit axetic:
CH3CHO + O2 CH3 C O CH3COOH + O
O OH
+ Oxy nguyn t tip tc oxy ha axetaldehyt thnh axit axetic:
CH3CHO + O CH3COOH Phn ng oxy ha axetaldehyt c th tin hnh trong pha hi hoc pha lng .Phn ng tin hnh trong pha hi khng cn khng cn xc tc nhng phn ng ta nhiu nhit nn d xy ra un nng cc b lm cho phn ng to nhiu sn phm ph do axetaldehyt b oxy ha su .Mt khc hi axetaldehyt to vi khgn kh hn hp n trong gii hn rng .Chnh v vy m trong thc t t ding phng php ny.
Ngi ta hay tin hnh oxy ha axetaldehyt trong pha lng c mt xc tc .Cc xc tc hay dng l hp cht ca cc kim loi coban,mangan,vanadi.Trong qu trnh phn ng th nhit l yu t nh huwongr nhiu n qu trnh.Cht oxy ha thng hay ding l oxy hay khgn kh c nit,nit ko theo axetaldehyt ra ngoi
Trong cng nghip thng dng hn hp xc tc Co(Mn):Cu vi t l 1:(1:3), ngoi ra cn thm vo qu trnh etyl axetat to vi nc hn hp ng ph tch nc ra khi phn ng. Sn phm ph khi oxy ho axetaldehyt metyl axetat, etyliden di axetat, axit formic v CO2.
Trong thc t ngi ta thng tin hnh tng hp axit axetic t axetaldehyt bng hai cng ngh sau:
+Tng hp axit axetic trong pha lng vi xc tc l axetat mangan.
+Tng hp axit axetic thi vi anhydric axetic.
Phng php tng hp axit axetic trong pha lng vi xc tc l mangan axetat s c a ra trong phn sau. Sau y l cng ngh sn xut ng thi anhydric axetic v axit axetic.III.1.Bn cht v iu kin phn ngTrong iu kin oxy ho aldehyt th song song vi axit cacboxylic cng nhn c anhydric.
+ 0,5O2 CH3COOH
CH3CHO
+0,5O2 0,5 (CH3CO)2O + 0,5 H2O
Do khi to thnh anhydric khng km hm c s cng nc nn gy ra kh nng thu phn n thnh axit. Mt trong cc iu kin tng hp ng thi alhydric v axit l tch loi nc nhanh. lm c iu ny ngi ta thng s dng cc cht ph ng ph (etyl axetat, di-isopropyl ete) nhng v sau ngi ta xc nh l c th khng cn chng. Lc cc yu t chnh iu chnh hiu sut gia axit v anhydric s c to ra bi:
+Thnh phn ca cht xc tc ng th c th l hn hp mui Co hay Mn vi cc mui ng(Co + Cu; Mn + Cu) theo t l tng ng 1:(1:3) hay thm ch l dng nng ca n ln trong dung dch phn ng ny.
+ S dng cht oxy ho kh long (7(9%) phn th tch oxy v tin hnh qu trnh oxy ho trong vng khuych tn hay gn vi n (s lm gim nng ca axit trong pha lng v lm tng nng cc gc t do CH3-C(=O m thng qua n to ra anhydric).Trong cc iu kin ny, t l gia axit v alhydric to thnh c th thay i n(3(5):(7(5).
tng hp ng thi ngi ta s dng hai phng php. Phng php th nht qu trnh c tin hnh trong thp sc kh vi mi trng l etyl axetat 50(700C v 0,4Mpa. S oxy ho c gy ra bi khng kh (khng phi bi oxy) vi xc tc to ra t axetat ca Cu v Co theo t l 10:1 hay 2:1. Dung mi, axetaldehyt v dung dch cht xc tc s a lin tc vo thp oxy ho, cn khng kh th sc qua hn hp phn ng. Hi thot ra cng vi khng kh c ngng t trong thit b ngng t hi lu, nc s tch ra cn etyl axetat th a tr v thp, axetaldehyt d bay hi s c hp th bng nc t kh, sau ti sinh n b phn chng tch hn hp dung mi vi nc v axetaldehyt cha phn ng. Sau trong cc thp khc s tip tc chng tch ln lt axit axetic, anhydric axetic, cn dung dch xc tc th a tr li giai on oxy ho.
vi phng php th hai, s oxy ho thc hin 55(600C khng dng dung mi l ho tan cc cht xc tc (v d axetat ng v coban theo t l 3:1) vi tc nhn oxy ho l khng kh thiu oxy (7(9% th tch oxy). Trong thit b phn ng dng thp c cha cc ng xon lm ngui, ngi ta a vo hn hp khng kh vi dng kh tun hon cha hi axetaldehyt. Hn hp phn ng gm ch yu l axit axetic, anhydric axetic cng vi cht xc tc ho tan trong n. c im ni bc ca phng php ny l a vo thit b phn ng mt lng ln kh qua c cu phn phi kh c bit nhm to ra kh nng khuy trn mnh cht lng. Cc sn phm c tch ra ( dng kh) cng vi kh bay ln. Cn dung dch cht xc tc nm li trong thit b phn ng v lm vic trong chu k sau, hu nh n khng b mt hot tnh.
Khng kh tinh khit ban u c nn trong my nn khng kh (1) di p sut ln hn p sut kh quyn khng nhiu v c trn vi khng kh hi lu c cha hi axetaldehyt. Hn hp va thu nhn 7 ( 9% (phn th tch) oxy; 25 ( 30% (phn th tch) axetaldehyt; 1% (phn th tch) axit axetic, cn li l nit] s cho vo thit b phn ng (2) qua mng li phn phi v sc qua dung dch cht xc tc, sao n li theo hi ca cc sn phm. Hn hp kh hi c lm lnh tc thi bng nc trong thit b ngng t (3) v hi lu. Phn ngng t v thit b phn ng trong cc cht c duy tr thng xuyn dng lng. Sau tin hnh lm ngui tip tc trong thit bngng t (4) v thit b bo ho (5), do axetaldehyt c a vo nn n c un si, cn cc sn phm th c ngng t t kh.
Hn hp hi kh pha trn thit b bo ho (5) qua my nn kh c a tr v trn vi khng kh nguyn liu v sau a vo thit b phn ng. Tt nhin, phn kh d c th loi b khi h thng khng lm long qu mc hn hp phn ng. Kh tch ra ny cha lng ln axetaldehyt c ra trong thp lc kh (7) bng lng nh axit axetic ( hp ph hi anhydric axtic) v sau ra trong thp hp th (8) bng nc thu ton b hi axetaldehyt. T dung dch nhn c trong thp chng phn on (10). Cng vi thit b ngng t hi lu nc mui (11) s ti sinh c axetaldehyt v sau a tr v thit b bo ho (5) v thit b phn ng. Khng kh sau lm vic s a v kh quyn qua thp hp th (8).
Phn ngng t sau thit b bo ho (5) v thit b lc (7) s chy vo b cha (12). Sn phm th ny cha 58 ( 60% (phn khi lng) alhydric axetic, 28 ( 30% (phn khi lng) axetic axetic, 9 ( 10% (phn khi lng) nc, 1 ( 1,2% (phn khi lng) etyliden axetat v mt lng nh axetaldehyt, formandehyt.
Do kh nng thu phn alhydric axetic ( c bit nhit cao) trong phng php 1 nn ngi ta tin hnh chng ng ph nc cng vi etyl axetat trong thit b (13) vi thit b ngng t hi lu (14) v thit b phn ly (15). Sau t hn hp sn phm thp (16) s tch c etyl axetat v a tr v thp (13). Axit axetic v alhydric axetic nhn c dng tinh khit sau khi chng phn on tip tc ( trn s khng biu din). Hiu sut sn phm t 95% theo l thuyt.IV.Qu trnh sn xut Axit axetic bng phng php oxy ho axetaldehyt trong pha lng.
IV.1. C ch phn ng
C ch ca qu trnh oxy ho axetaldehyt to thnh axit axetic l c ch to gc t do, sinh ra axit peraxetic l sn phm trung gian (phng trnh22)
Axit peraxetic sau c th phn ng vi axetaldehyt to thnh axetaldehyt monoperaxetat (AMP). AMP b phn hu nhanh chng thnh Axit axetic nh s chuyn dch hydro trong phn ng Bayer Villiger. Ngoi ra cn xy ra s chuyn dch gc metyl to metyl format:
S chuyn dch ca nhm alkyl tr nn d dng hn nhiu i vi cc aldehyt cao hn, c bit l nu c nhnh v tr (.
S tt mch ch yu xy ra theo phn ng lng phn t ca cc cht trung gian teroxit.
Phn ng (24) l ngun gc ch yu ca: CO, metanol, formaldehyt v axit formic - cc sn phm ph ca qu trnh oxy ho axetaldehyt. Qu trnh oxy ho khng c xc tc c th l iu kin c hiu qu cho qu trnh chuyn ho axetaldehyt mc thp duy tr nng axedehyt trong phn ng. iu ny gi trng thi n nh nng gc axetyl peroxit mc thp thun li phn ng (22), v vy hn ch xy ra phn ng lng phn t (24). Trong phn ng khng c xc tc cn c bit ch khng ch nng ca AMP khng vt qu gii hn n.
Phn ng phn hu gc t do khc c th tr nn quan trng nhit cao hoc khi nng oxy thp:
Tc ca phn ng decacbonyl ho tng khi nhit tng, tuy nhin n ch tr nn quan trng khi oxy khng lc sch cc gc axetyl (phng trnh 21).
IV.2.Xc tc
Xc tc c mt vai tr quan trng trong qu trnh oxy ho axetaldehyt. Chng phn hu cc peroxit v do hn ch ti thiu nguy c n. Tuy nhin tnh hung din ra phc tp hn iu ny. Xc tc mangan l loi xc tc c a thch hn c c chc nng quan trng l gim bt cc gc axetyl peroxit.
Phn ng (25) tr gip phn ng (22) trong vic trit nng gc axetylperoxit. Ion Mn(III) sinh ra trong phn ng (25) c th thc hin chc nng ca gc axetylperoxit trong phn ng (22) (th hin phng trnh 26) nhng khng gp phn lm gim hiu qu phn ng (24).
Mangan thm ch cn lm tng rt tt tc ca phn ng gia axit peraxetic v axetaldehyt to thnh axit axetic. Phn ng khi c mt mangan trc tin cn ch ti peraxit, aldehyt v mangan. Tc ny cao hn nhiu so vi tc to thnh AMP khng c xc tc, do mangan c th xc tc s to thnh AMP v phn hu AMP. Nhiu kh nng mangan c th xc tin mt c ch khc khng cn AMP (khng pht hin thy AMP trong qu trnh oxy ho c xc tc mangan).
ng c th c tc dng tng h vi xc tc mangan. Mt vi kha cnh ph nh c tnh xc tc tt ca mangan nu trn. Vn ch yu y l tc phn ng tng rt ln. Mt phn ca l do ny c th do mangan to ra trung tm phn ng m hoc tc nhn khi mo chui (ion Mn3+) bng phn ng vi axit peraxetic:
Kt qu l tc phn ng tng rt cao lm cho vn thiu oxy tr nn nghim trng, nng gc t do trng thi dng tng ln v t nht khi phc mt phn tham gia ca phn ng (24). c bit l i vi cc andehyt cao hn nhng khng phi lun ng cho mt s phm vi no ca axetaldehyt.
Tuy nhin, ion Cu2+ c th oxy ho gc axetyl rt nhanh:
Ion axetyl c th phn ng nh sau:
Nhiu loi xc tc c cp, trong Co c dng thng xuyn nhng dng nh c hi km hn Mn. Mt vi tc ng ca Co khng xut hin c th hiu d dng. Hn hp Co v Mn rt thch hp khi yu cu sn xut lng ln anhydrit
IV.3. Cc yu t nh hng n qu trnh
a. nh hng ca nguyn liu u
Axetaldehyt Do axetaldehyt d b bin i thnh paradehyt, khi bo qun mt lng nh axetaldehyt cng b bin i. Do lm cho sn phm ca qu trnh khng tinh khit, c ln nhiu tp cht, gy kh khn cho vic tinh ch v lm sch sn phm.
Cng mt iu kin oxy ho v xc tc axetaldehyt c th b bin i thnh nhiu sn phm khc nhau:
CH3CHO + 0,5 O2 ( CH3COOH
2CH3CHO + 3/2O2 ( CH3COOCH3 + H2O + CO2
3CH3CHO + O2 ( CH3CH(OCOCH3)2 + H2O
CH3CHO + 2O2 ( HCOOH + H2O + CO2
CH3CHO + 5/2O2 ( 2CO2 + 2H2O
Khc phc cc hin tng ny bng cch khng ch nghim ngt ch oxy ho, dng xc tc thch hp v s dng axetaldehyt >99%, khng qu 1%paraldehyt.
Hm lng ca axetaldehyt c nh hng ln n s to thnh axit peraxetic, nu hm lng axetaldehyt trong thit b oxy ho tng ln qu mc th lng peraxit to thnh gim xung. Cn nu gim hm lng axetaldehyt th lm tng lng peraxit trong vng phn ng v giai on 1 to peraxit nhanh hn giai on 2, iu ny dn n s tch t axit peraxetic s khng c li cho qu trnh v d gy n. V vy cn phi khng ch hm lng axetaldehyt thch hp khi cho vo.
Oxy
Vn tc oxy ho khng ph thuc vo nng oxy m ch ph thuc vo tc ho tan kh O2 vo khi lng
b. nh hng ca xc tc
Vai tr ca xc tc s dng cho qu trnh oxy ho axetaldehyt l lm tng tc phn ng v hng phn ng theo chiu to sn phm chnh v m bo s tri qua ca tt c cc giai on vi tc nh nhau.
Cc xc tc nh axetat ca st, ng, coban u lm tng s oxy ho axetaldehyt thnh axit peraxetic, nhng lm chm tc ca giai on to thnh anhydric axetic do mt khi lng axit peraxetic tch t li trong thit b phn ng gy n.
Mt khc khi s dng hn hp axetat ca ng coban lm xc tc v tin hnh trong mi trng c dung mi l etyl axetat th c th nhn c axit axetic cng vi anhydrit axetic, v hiu sut anhydrit axetic ln hn do etyl axetat c kh nng to hn hp ng ph vi nc, lm tch nc ra khi qu trnh. iu ny chng t hiu sut ca sn phm chnh ph thuc vo bn cht ca xc tc.
Xc tc tt nht cho qu trnh l axetat mangan cho hiu sut sn phm chnh cao, khc phc c nhc im ca cc xc tc k trn, c kh nng ti sinh axit peraxetic. c bit l hn hp xc tc ca axetat mangan-coban c hot tnh v chn lc cao do c s t hp tng tr ln nhau.
Hm lng xc tc c mt trong khi lng c nh hng n vn tc oxy ho. Khi tng nng xc tc th tc phn ng khng tng hoc tng rt chm. Gii hn nh l 0,05 n 0,1% trng lng.
c. nh hng ca nhit
Yu t quan trng nh hng n nhiu qu trnh oxy ho axetaldehyt chnh l nhit . Tng nhit s thc y c cc giai on phn ng, c bit l phn ng phn hu axit peraxetic. Qu trnh oxy ho pha lng axetaldehyt thng c tin hnh trong khong nhit 65 ( 75oC. Nhit rt thp hn s dn ti s tch t hp cht peraxetic trong phn ng v pht sinh hin tng n. Nu nhit tng tc phn ng chnh song cng thc y cc phn ng ph, c bit l phn ng oxy ho hon ton axetaldehyt. Vic tng nhit cng gy nguy him v hi axetaldehyt bay ln to hn hp n vi oxy trong gii hn rng. Do vic tng nhit li phi i km vi vic tng p sut. duy tr nhit trong thit b trong khong nh vy ngi ta phi rt bt nhit phn ng bng cch tin hnh oxy ho trong thit b dng thp trong t cc ng xon lm lnh.
d.nh hng ca p sut
p sut t nh hng n qu trnh. Nhng trong thc t t ngi ta thc hin qu trnh p sut 3 ( 4 at, l iu kin cn thit gi axetaldehyt trong dung dch nhit phn ng do axetaldehyt l cht lng rt d bay hi m iu kin lm vic i hi phi tin hnh trong pha lng nn gi cho axetaldehyt trng thi lng ti nhit phn ng (60 ( 70oC). Nu s dng p sut cao qu th s gy tn km cho vic ch to thit b.
e.nh hng ca lng nc Lng nc trong thit b phn ng c nh hng ti hiu sut thu sn phm. Khi lng nc gim th dn n tng s to thnh sn phm ph anhydrit axetic ng thi hiu sut sn phm chnh gim do vn tc ca spu thu phn anhydrit axetic gim. Khi lng nc tng th hm lng axit peraxetic tng v hiu sut sn phm chnh tng, tuy nhin nu lng nc tng qu trnh s lm pha long sn phm, gy kh khn cho qu trnh tinh ch sau ny.V.Phng php vi sinhBn cht ca phng php ny l oxy ho ru etylic bng oxy khng kh nh enzim ca vi sinh vt axetobacter (cn gi l xc tc sinh hc) lm tng tc phn ng.
C 4 phng php ln men ru etylic thnh axit axetic: Ln mem chm, ln mem nhanh, ln mem chm v ln mem hn hp. Phng php ln mem chm l phng php c truyn hin nay c ng dng ln mem dm n.
Qu trnh ln mem ru etylic thnh axit axxetic qua 2 giai on di tc dng ca enzim alcohol oxydaza trong vi khun axetobacter v oxy khng kh. Qu trnh ny thc cht l qu trnh oxy ho lin tip etanol thnh axetaldehyt ri thnh axit axetic.
+ Giai on 1: oxy ho etanol thnh axetaldehyt sau thnh hydrat axetaldehyt.
+ Giai on 2: oxy ho hydrat axetaldehyt thnh axit axetic.
Qu trnh ln men axit axetic l qua trnh hiu kh. V vy phi m bo khng kh tt, lng oxy cn thit trnh to phn ng ph. Mt khc, mi trng phi ru (nng ru phi bo m) trnh axit axetic b oxy ho hon ton to kh CO2 v H2O.
Tu theo cc loi vi sinh vt c dng lm xc tc khc nhau m nng axit axetic t c cng khc nhau.
VI. Phng php ho hc g
Khi nhit phn g ngi ta thu c mt hn hp lng v hc n lng xung. Hn hp ny l dung dch ca nhiu hp cht trong ch yu l axit axetic, ru metylic, metyl axetat, axeton v mt phn hc n ho tan do s c mt ca axit axetic v mt s cht khc. Thnh phn ca hn hp cht lng ny ph thuc vo ging, cht lng v m ca g.
Ni chung phng php sn xut axit axxetic bng phng php nhit phn g cho hiu sut sn phm khng cao, tinh khit thp.VII. Cc phng php tng hp khcNgoi cc phng php sn xut axit axetic nu trn th cc nh khoa hc cn a ra mt s phng php khc nh: phng php oxy ho sec-butyl axetat trong pha lng, oxy ho etylen trong pha hi v oxy ho trong pha kh cc hydrocacbon no m ch yu l n-butan. Tuy nhin, cc phng php trn u mi ch dng li nghin cu m cha a ra c cng ngh vo sn xut.
VIII. So snh cc phng php sn xut axit axetic
Ni chung cc phng php sn xut axit axetic ni trn th mi phng php c u nhc im ring m da vo cc nh cng ngh s la chn phng php tt nht ph hp vi yu cu ca mnh.
so snh cc phng php, ta xt v mt hiu qa ca qu trnh v c bit l gi thnh sn phm.
i vi phng php sn xut i t axetaldehyt. Hiu sut qu trnh rt cao thng t 95-98%. Tuy nhin phng php ny c nhc im l gi thnh sn phm qu cao do s dng ngun nguyn liu t tin. c bit khi s dng axetaldehyt t qu trnh oxy ho axetylen th gi thnh cng cao. Hn na do axetylen l cht ho hc him, khng c trong t nhin m phi qua tng hp. Xu hng hin nay ngi ta khng dng axetylen m s dng etylen tng hp axetaldehyt do etylen l cht c sn trong kh du m v kh thin nhin. Do n lm gim rt nhiu gi thnh sn phm.
Phng php oxy ho c iu chnh parafin thp (butan v ng ng). Phng php ny cho hiu qu kinh t cao v s dng cht sn c, r tin. Gi thnh ca axit axetic nhn c t oxy ho butan thp hn khong 30% so vi sn xut t axetaldehyt. Hiu sut sn phm tng i cao.
Phng php sn xut i t metanol v CO cng l mt phng php kinh t v mi hn c do c th tng hp metanol t du m v than l nhng ngun ti nguyn kh di do.
Phng php oxy ho n-butan th hay dng hn phng php oxy ho naphta do khi oxy ho naphta c nhiu sn phm ph nn tn km cho vic x l, tinh ch sn phm axit axetic.
Tuy nhin, phng php tng hp axit axetic t oxy ho axetaldehyt vn l phng php ti u. c bit l phng php ny c th iu ch chung axit axetic v alhydric axeticIX. Nng cao nng v tinh ch Axit axetic
IX.1.Nng cao nng v tinh ch axit axetic
Hnh 7: S nng cao nng axit axetic theo Otherm Sn xut xenlulo axetat v cc sn phm khc nh cht n RPX v cc qu trnh khc s dng axit axetic nh l dung mi, sn sinh lng ln axit axetic long (khong 28%) l sn phm ph. Thu hi axit t dung dch long c th thc hin bng chng thng thng, chng luyn ng ph, chng trch ly, trch ly bng dung mi. Chng trc tip i hi thp chng chiu cao ln gm nhiu a, dng hi lu ln. Cc qu trnh khc s dng c chng v trch ly c chng minh v s dng trong thng mi gim gi thnh nng cao nng axit. Vo nhng nm 1970, ngi ta cp n phng php chng bng mui. Biu hin chung ca c ba qu trnh chng ng ph, trch ly v chng bng mui l s c mt ca cu t phn ly. Tc dng ca cu t phn ly l lm thay i hot ca cc cu t trong hn hp v lm thay i ng cn bng cho php tch cc cu t d dng. Chng ng ph nht thit cu t phn ly phi c kh nng to vi mt hay nhiu cu t hn hp ng ph c nhit si nh i ln nh, c ti liu ni c th chn cu t phn ly to vi mt trong hai cu t ca h hn hp ng ph c nhit si cao v i xung y thp. Trong trng hp tch nc ny, nu tc nhn tch khng ho tan vi nc, th n c th d dng tch ra khi nc v tun hon tr li. Este, ete, benzen c chng minh l cu t phn ly.
Chng bng mui mi xut hin, c nhiu trin vng nhng cha c nghin cu hon chnh, chng bng mui c u im l cu t phn phn ly th rn khng bay hi nn cht lng sn phm cao. S cu t phn ly trong nh pha hi s t hn trong pha lng, c th chn loi mui CH3COONa hoc CaCl2, nu dng CH3COONa th thu c axit axetic c a mt lng nc ln nht nn tiu tn nng lng, hiu qu chng thp. Nu dng CaCl2 v mt k thut axit thu c >90% l c th, tuy nhin hon nguyn mui cn nhng ch tiu kht khe. Mt trong nhng qu trnh tch nc ni bt c pht trin bi Otherm. y l qu trnh kt hp trch ly v chng ng ph diu ny gim c s tiu tn hi nc. Trong qu trnh ny dung mi (1) un si 102- 1050 C c s dng trch axit t dung mi ca n theo c ch c hc. Lp nc cha khong 0,1% axit axetic vaf 0,2% dung mi, c a v thp nh (4), nc c thi ra nh cht thi. Lp trch cha lng ln dung mi, axit, nc c cung cp cho thp chng ng ph chnh(8). Dng ng ph c tch thnh hai lp trong thit lc (9). Lp trn gm thc cht l dung mi nguyn cht v n c hi lu tr li thp chng ng ph bng hi lu. Lp thp hn (11) cha lng nh axit v dung mi c quay tr li thit b trch ly tai im thch hp (12), ti axit axetic c nng tng t. Dng chy ra ca thp chng ng ph l axit mnh v dung mi (13) c a vo thit b tinh ct (14), ti y a ra sn phm axit bng (15), v dung mi quay tr li thit b cha ti s dng. Bng cch tng s lng a ca thp chng ng ph nc cha trong lp nc c th gim xung, tuy nhin chi ph cho vic tng s a ln li ln hn chi ph cho vic thm lng cht trch ly.IX.2.Cht lng sn phm
C mt ch s quan trng trong ch tiu thng mi ca axit axetic M. nhng ni khc, ba hoc nhiu hn ch s c xc nh. S khc nhau c bit l kim loi nng, clorua, sunfat, asen v st.
Bng 8:Cc c tnh thng mi ca axit axeticc tnh thng mi Gii hn
Axit axetic, %kl min 99,85
Trng ln ring, 20/200C - 1,0505 - 10520
Phm vi chng, 0C
im si u min 117,3
im kh max 118,3
Nhit ng c, 0C min 16,35
Mu sc, n v Pt Co max 10
Lng nc cha, % kl max 0,15
Axit formic, %kl max 0,05
Andehyt(v d axetaldehyt) max 0,05
St, ppm max 1
Kim loi nng max 0,05
Clorua, ppm max 1
Sunfat, ppm max 1
Axit Sunfur max 1
Chng IVcng ngh SN XUT AXIT AXETIC BNG PHNG PHP OXY HO AXETALDEHYT TRONG PHA LNG C XC TC
Dy chuyn sn xut axit axetic thc hin cc cng on sau: Oxy ho axetaldehyt
Tinh ct sn phm th
Loi cc tp cht ra khi sn phm
I.Giai on oxy ho axetaldehyt
Giai on ny tin hnh trong thit b oxy ha, ngy trc oxy ho axetaldehyt ngi ta s dng thit bi lm vic gin on. Ngy nay do yu cu nng sut ln ngi ta ch to thit b lm vic lin tc, nng sut c th t ti 20 30 tn trong mt ngy m. C hai loi thp, tuy nhin thit b dng ph bin hin nay l thp kiu si bt, loi ny n gin v thch hp cho phn ng kh lng. Axit axetic dng lm mi trng trong xy ra s oxy ho. Thp cha dung dch phn ng, kh cho vo phn nhiu y thp qua b phn to thnh bt nh phn b u khp tit din ca thp, phn nh thp c ng knh ln hn gim vn tc kh. Phn di ca thit b c ng knh 1m, c chiu cao khong 12m chia lm 5 on, trong tng on c t ng xon rut g lm bng nhm, cho nc lnh tun hon rt nhit phn ng (tng b mt truyn nhit 200m2). Cc ng xon ny cn c tc dng nh m lm tng b mt tip xc gia axetaldehyt v oxy c th iu chnh qu trnh oxy ho d dng ngi ta cho oxy vo tng on thp tr hai on u. Mun cho qu trnh oxy ho xy ra bnh thng, cn phi khng ch chnh xc lng axetaldehyt, axit axetic, oxy, xc tc, khng ch nghim khc nhit ca qu trnh, trnh n on trn thng xuyn cho oxy vo. Nhit c th duy tr 60 -700C mi on v theo chiu cao thp, mi on c li ngn ng th ho pha lng trnh hin tng qu nhit cc b v cc phn ng ph to sn phm khng mong mun. Cng vi axetaldehyt vo cn c c xc tc sao cho hm lng khong 0,075%, lu lng oxy vo khong 270 m3/h p sut 4 at Sn phm lng ly ra phn m rng, hn hp kh bao gm CO2, N2, O2 v mt phn axetaldehyt d tch ra nh, hi cht lng do dng kh mang ra c ngng t v quay tr li thit b oxy ho.
u im ca thit b si bt ny l b mt tip xc pha ln, lp lng c khuy trn mnh. Vt liu ch to thp kiu ny c th dng thp crom, niken molipden hoc cc loi thp khng g khc.
II.Giai on tinh ct sn phm th
Mc ch ca cng on ny l loi cc sn phm khng cn thit thu axit c da vo tnh cht l hc. Giai on ny tin hnh trong cc thp chng ct.
Thp chng 1 tch cc cu t d bay hi, c nhit si thp hn axit axetic nh: axit formic, axetaldehyt, metyl axetat. Thp chng 2 c nhim v tch axit axetic ra khi sn phm nng c nhit si cao hn nh: axetat mangan, etyliaxetat, cc sn phm nha.III.Giai on lm sch axit axetic
Mc d qua hai thp chng ct loi sn phm ph khng mong mun tuy vy vn cha tch c trit , trong sn phm cn c th c nhiu tp cht khc vi hm lng nh. V vy thu c axit axetic c tinh khit cao ngi ta tin hnh qu trnh oxy ho lm sch.
Cht oxy ho thng dng lm sch axit axetic l KMnO4. Nu dng KMnO4 d c th mt mt mt lng axit axetic theo phn ng: 2KMnO4 + 6CH3COOH (2Mn(OCOCH3)2 + 2CH3COOK +3H2O +5/2O2Trong dung dch cha H2SO4, KMnO4 oxy ho HCOOH to thnh CO2:
KMnO4+ HCOOH ( 5CO2 +8H2O + 2HCOOK + 2(HCOO)2MnIV. Dy chuyn sn sut axit axetic t axetaldehyt Dy chuyn sn sut axit axetic t axetaldehyt (Hnh 8) Thuyt minh: S dy chuyn sn xut axit axetic bng phng php oxy ho axetaldehyt trong pha lng.
Dung dch xc tc c chun b trong thit b (1) bng cch ho tan axetat mangan trong axit axetic. Dung dch ny cho qua thng cha trung gian (2), sau trn cng vi CH3CHO c lm lnh bng nc mui b cha (3). Hn hp c bm (20) np vo phn y ca thp oxy ha (4) p sut 4at. Oxy k thut c a vo dc thn thp khong 4 n 5 v tr khc nhau i qua ng phn phi c bit tng chuyn haca qu trnh v ng thi cng tng tc phn ng.Ct thp c np cht lng n gn phn n rng. Cht lng cng chuyn ng ln cao nng axit axetic cng tng v nng axetaldehyt cng gim. y thp phn hp duy tr nhit 600C v p sut 3,8 - 4at, cn trn nh thp gi nhit l 750C v p sut l 2,8-3at. Vic khng ch chnh xc nhit trong thp phn ng c mt ngha ht sc quan trng bi v khi nhit thp hn 60o( 700C th s dn n s tch t peoxyt, cn nhit cao hn n s thc y phn ng ph c bit l phn ng oxy ho hon ton axetaldehyt. pha long hn hp hi d gy n(trnh s tch t peraxit v oxy gy n) ngi ta cho nit lin tc vo phn trn cng ca ct thp.
Hn hp hi v kh t nh thp (4) i sang thit b ngng t lm lnh (5) ti y nhit l 20 - 300C nn hi axetaldehyt, axit axetic, nc ngng t, trong ho tan phn ln axetaldehyt cha phn ng, sau khi tch khi kh trong thit b phn ly (6) c a tr li thp oxy ha (4). Hi tch ra c ra trong thp ra (7) bng nc tch ht phn axetaldehyt d v axit axetic, ri thi ra ngoi tri.
Sn phm th ly ra lin tc t phn n rng ca ct thp oxi ho qua mng cnh sn v a vo thp tinh ch(8), ti y cc hp cht nh b ui ra v ngng t (10) , mt phn hi lu v thp tinh ch, phn cn li qua thit b ngng t lm lnh(11) ri vo b phn thu gom(12) v a I x l tip.
Axit axetic c loi b cc hp cht nh c a vo thit b un si(13) ri vo thp (14) chng ct ln (2), ti nhit 1250C, axitaxetic bay hi, tch ra khi xc tc, paradehyde.... v c ngng t trong thit b hi lu (15), mt phn axit axetic tc ra a tr li thp(14),mt phn axit axetic a v thit b (1) chun b xc tc,cn li phn ln a I lm sch ti thit b (16). y c lm sch bng KMnO4 oxy ho cc tp cht.
Ngi ta cho bay hi axit axetic mt ln na trong b phn un bc hi (17) ti 120 1250C tch axetat mangan to thnh, hi i qua thp m(18) lc sch mt ln na ri mi qua thit b ngng t (19) cho axit axetic thng phm.V.Thit b oxy ho axetaldehyt(hnh 9)Phn IITnh ton
Thit k phn xng sn xut axit axetic nng sut 45000 tn/nm theo phng php oxy ho axetaldehyt trong pha lng vi xc tc ban u l axetat mangan.
I.Cc s liu ban u.
Nng sut ca phn xng sn xut : 45000 Tn /nm
Nguyn liu ban u :
Axetaldehyt : 99,3 % trng lng
Paraldehyt : 0,2 % trng lng
Axit axetic : 0,25 % trng lng
Nc : 0,25 % trng lng
Hiu sut chung ca qu trnh : 98 %
Tn tht axit axetic : 2 %
Thnh phn ca xc tc lng :
Axetat mangan : 6 % trng lng
Axit axetic : 70 % trng lng
Nc : 24 % trng lng
iI.Tnh ton cho thit b oxy ho
II.1.Cn bng vt cht
II.1.1. Tnh thi gian lm vic ca thit bChn thit b chnh l thit b oxy ho kiu si bt lm vic lin tc khng ngh ngy l v ch nht. Thit b ch ngh lm vic khi cn phi sa cha.
Thi gian lm vic c tnh theo cng thc :
Ttt = T - Tngh
Trong :
Ttt : l s ngy thc t lm vic ca thit b trong nm.
T : l tng s ngy lm vic trong nm ( 365 ngy).
Tngh: l thi gian ngh kim tra, duy tu, sa cha v bo dng thit b.
Trong mt nm c 365 ngy th dnh:
+ 15 ngy cho vic kim tra, sa cha nh.
+ 20 ngy cho cng tc duy tu, bo dng, thay th v sa cha ln.
S ngy lm vic trong mt nm l:
365 - (15 + 20) = 330 ngy.
Vy s gi lm vic trong mt nm l:
330 24 = 7920 gi.
II.1.2. Tnh tiu hao nguyn liu
Lng axit axetic m thit b sn xut trong mt gi l:
(Kg/h).
Tuy nhin, do tn tht axit axetic l 2% nn nng sut thc t ca thit b oxy ho phi l:
EMBED Equation.3 (1 + 0,02) = 5795,456 (Kg/h).
Khi tin hnh oxy ho axetaldehyt s xy ra cc phn ng sau:
CH3CHO + 1/2O2 CH3COOH (1)
2CH3CHO + 3/2O2 CH3COOCH3 + CO2 + H2O(2)
3CH3CHO + O2 CH3CH(OCOCH3)2 + H2O(3)
CH3CHO + 2O2 HCOOH + CO2 + H2O(4)
2CH3CHO + 5O2 4CO2 + 4H2O(5)
Theo phn ng (1) ta tnh c lng axetaldehyt cn thit to thnh 5795,456 kg axit axetic trong mt gi l :
(kg/h).
Tuy nhin, do nguyn liu cha 99,3% axetaldehyt v hiu sut chung ca qu trnh l 98% nn tng lng axetaldehyt k thut cn a vo thit b l : (Kg/h)
Vy thnh phn ca nguyn liu u l:
Axetaldehyt : 4367,306 0,993 = 4336,735 (Kg/h)
Paraldehyt : 4367,306 0,002 = 8,735 (Kg/h)
Axit axetic : 4367,306 0,0025 = 10,918 (Kg/h)
Nc : 4367,306 0,0025 = 10,918 (Kg/h)
II.1.3.Lng axetaldehyt chuyn haPhn ng (1) axetaldehyt chuyn ha ht 98% trng lng.Cn li 2% c th chuyn ha theo cc phn ng nh sau:
+Vy lng axetaldehyt chuyn ha theo phn ng (1) l:4250 Kg/h
+Phn ng (2):0,5%
Vy lng axetaldehyt chuyn ha l:4336,7350,005 =21,684 (Kg/h)
+Phn ng (3):0,35%
Vy lng axetaldehyt chuyn ha l:4336,7350,0035 =15,179(Kg/h)
+Phn ng (4):0,075%
Vy lng axetaldehyt chuyn ha l:4336,7350,00075 =3,253 (Kg/h)
+Phn ng (5):0,075%
Vy lng axetaldehyt chuyn ha l:4336,7350,00075 =3,253 (Kg/h)
+Cn li 1% cha phn ng.
Lng axetaldehyt cha phn ng:4336,735 0,01=43,37 (Kg/h)
Trong gi thit 50% lng axetaldehyt tch theo pah hi ,cn li 50% lu li trong pha lng.
CH3CHOd (l):0,5 43,37 =21,685 (Kg/h).
CH3CHOd(h):0,5 43,37 =21,685 (Kg/h).II.1.4.Tnh lng xc tc lng a vo
Trong cng ngh oxy ho axetaldehyt xc tc axetat mangan thng dng 0,05- 0,1% so vi nguyn liu. Vy ta chn xc tc axetat mangan so vi nguyn liu l 0,08% (trng lng).
Gi lng xc tc lng a vo thit b oxy ho l X (Kg/h) th lng axetat mangan trong l 0,06.X (Kg/h ).
Tng lng dung dch oxy ho ( gm hn hp axetaldehyt k thut v xc tc lng ) l:
4367,306 + X ( Kg/h )
T , ta c phng trnh :
0,06.X = 0,0008.( 4367,306 + X)
Suy ra X = 59,018 (Kg/h )
Vy thnh phn xc tc gm:
Axetat mangan : 59,0180,06 = 3,541 (Kg/h )
Axit xetic : 59,0180,7 = 41,313 Kg/h )
Nc : 59,018 0,24 = 14,164 (Kg/h )
II.1.5. Tnh lng oxy cn thit a vo thit b
Lng oxy k thut cn thit a vo thit b bng tng lng oxy tham gia vo cc phn ng oxy ha (6 phn ng).
Lng oxy dng cho phn ng (1) l: (Kg/h)
Lng oxy ca phn ng (2): (Kg/h)
Lng oxy ca phn ng (3): (Kg/h)
Lng oxy ca phn ng (4): (Kg/h)
Lng oxy ca phn ng (5): (Kg/h)
Tng lng oxy cn l:
1545,455+ 11,828 + 3,68 + 4,732 + 5,915 = 1571,610 (Kg/h)
* Gi s oxy dng trong qu trnh oxy ha l oxy k thut c tinh khit 99 % v chuyn ha l 98%. Vy lng oxy k thut dng trong cho qu trnh l:
(Kg/h)
Thnh phn ca oxy k thut l:
O2 :
EMBED Equation.3 0,99 = 1603,683 (Kg/h)
N2 :
EMBED Equation.3 0,01 = 16,199 (Kg/h)
- Lng oxy k thut cn d sau phn ng:
1571,610 = 48,272 (Kg/h)
II.1.6. Tnh lng cc sn phm ph to thnh
+Phn ng (2):- Lng CH3COOCH3 l: (Kg/h)
- Lng CO2 l: (Kg/h)
- Lng H2O l: (Kg/h)
+ Phn ng (3):
- Lng CH3CH(OCOCH3)2 l: (Kg/h)
- Lng H2O l: (Kg/h)
+Phn ng (4):
- Lng HCOOH l: (Kg/h)
- Lng CO2 l: (Kg/h)
- Lng H2O l: (Kg/h)
+ Phn ng (5):- Lng CO2 l: (Kg/h)
- Lng H2O l: (Kg/h)
Tng lng axit axetic th ti u ra ca thit b oxy ha l:
5795,456 +10,918 +41,313= 5847,687(Kg/h)
Tng lng nc (nc c trong nguyn liu, trong thnh phn ca xc tc lng v nc to ra t cc phn ng oxy ha) c trong sn phm l:
10,918 + 14,164 + 4,435 + 2,070 + 1,331 + 2,662 = 35,58 (Kg/h)
Tng lng CO2 to ra trong qu trnh l:
10,842+ 3,253 + 6,506= 20,601 (Kg/h)
Bng cn bng vt chtNguyn liu voKg/hSn phm raKg/h
Axxetaldehyt k thut4367,306Sn phm lng
CH3CHO4336,735CH3COOH5847,687
Paraldehyt8,735CH3COOCH318,234
CH3COOH10,918CH(OCOCH3)216,789
H2O10,918HCOOH3,401
Xc tc lng59,018Paraldehyt8,735
(CH3COO)2Mn3,541H2O35,58
CH3COOH41,313CH3CHOd(l)21,685
H2O14,164(CH3COO)2Mn3,541
Oxxy k thut1619,882Sn phm kh
O21603,683CH3CHOd(h)21,685
N216,199O2d48,272
N216,199
CO220,601
Tng
6046,21Tng6046,21
II.2.Cn bng nhit lng
Vic tnh cn bng nhit lng gip ta xc nh lng nc cn thit cho vo lm lnh v cc phn ng xy ra trong thit b to nhit mnh. Theo nh lut bo ton nng lng ta c biu thc:
Tng nhit vo (Qv) = Tng nhit ra (Qr).
Vi : Qv = Q0 + Qp + Qn + Qhl
Qr = Qsp + Qll + Qm+ Qn
Q0: Nhit do nhin liu mang vo. (Kj/h).
Qp: Nhit ta ra khi phn ng. (Kj/h).
Qn: Nhit cn t nguyn liu ti nhit phn ng., (Kj/h).
Qhl: Nhit do axetaldehyt hi lu mang vo., (Kj/h).
Qsp: Nhit do sn phm mang ra, (Kj/h).
Qll: Nhit ly ra thng qua lm lnh , (Kj/h).
Qm: Nhit mt mt ra mi trng, (Kj/h).
Qn : Nhit tch ra do nng nhit ca CH3CHO hi lu li n nhit phn ng, (Kj/h).
II.2.1. Tnh lng nhit do nguyn liu mang vo.
Chn nhit ban u ca nguyn liu trc khi i vo thit b l 20oC.
Nguyn liu i vo gm c Axetaldehyt k thut, oxy k thut v dung dch xc tc lng do lng nhit do nguyn liu mang vo c xc nh bi cng thc:
Q0 = Q1 + Q2 + Q3 .
Trong :
Q1: Nhit lng do Axetaldehyt k thut mang vo, (Kj/h).
Q2: Nhit lng do oxy k thut mang vo, (Kj/h).
Q3: Nhit lng do dung dch xc tc mang vo, (Kj/h).
Nhit lng ca dung dch n cu t ti nhit t c xc nh bi cng thc:
Q = t.Ci.miTrong :
Q: Nhit lng do dung dch mang vo, (J/h).
t: Nhit ca dung dch, (oC).
Ci: Nhit dung ring ca cu t th i ti nhit ,(J/kg.oC).
mi: Khi lng ca cu t th i, (Kg/h).
a.Xc nh nhit dung ring ca cc cu t:+ Ti 20oC, tra bng ta c:
Cu tCp( Kj/Kg.0C)Cu tCp(Kj/Kg.0C)
CH3CHO1,38N2(4 atm)1,052
Paraldehyt2,043O2(4 atm)0,924
CH3COOH1,994H2O4,18
Nhit dung ring ca mt cht ho hc c xc nh bng cng thc:
M.C = n1.C1+ n2.C2 + n3.C3 + ...
M: khi lng mol ca mt cht, (Kg/Kmol).
C: Nhit dung ring ca hp cht ho hc, (J/kg.oC ).
n1, n2, n3: s nguyn t ca cc nguyn t trong hp cht.
C1, C2, C3: nhit dung nguyn t ca cc nguyn t tng ng, (J/Kg.oC).
Nhit dung nguyn t ca cc nguyn t cc nguyn t
Nguyn tTrng thi ca hp cht
RnLng
C
H
O
Mn7500
9638
16800
2600011700
18000
25100
33500
Nhit dung ring ca mangan axetat (C4H6O4Mn) l:
M.C = nC.CC + nH.CH + nO.CO + nMn.CMn
173.C = 411700 + 618000 + 425100 + 133500 = 288700
C = 1668,7 (J/Kg.oC) = 1,67 (Kj/Kg.oC)
Nhit lng do dung dch axetaldehyt k thut (gm CH3CHO, CH3COOH, paraldehyt v nc) mang vo:Q1
Q1 121398,953 (Kj / h).
Nhit lng do oxy k thut mang vo:
Q2 = 20.(1603,683 0,924 + 16,199 1,052)
Q2 = 29976,889 (Kj / h).
Nhit lng do dung dch xc tc mang vo:
Q3 = 20.(3,5411,67 + 41,3131,994 + 14,1644,18)
Q3 = 2949,942 (KJ/h)
Vy: Q0 = Q1 + Q2 + Q3 = 121398,953+29805,623 +2949,942
Q0 = 154325,784 (KJ/h).
II.2.2. Nhit lng dng un nng nguyn liu n nhit phn ng
Qn =t. Ci.mi
Trong :
Ci : nhit dung ring ca cu t th i ti nhit trung bnh ttb, (J/Kg.).
mi : khi lng ca cu t th i, Kg/h.Ta c : = t2 - t1 = 60 - 20 = 400C.Nhit dung ring ca cc cu t 400C
Cu toC (Kj/Kg.0C)Cu tC (Kj/Kg.0C)
CH3CHO1,38H2O4,175
Paraldehyt2,043N2(4 at)1,046
CH3COOH2,093O2(4 at)0,9272
Nhit lng cn t nng axetaldehyt n nhit phn ng:
Qna=40.(4336,735 1,38 + 8,735 2,043 + 10,918 2,093 + 10,918 4,175)
Qdna= 242838,957 (Kj/h).
Nhit lng cn t nng oxy k thut n nhit phn ng:
Qoo = 40.(1603,683 0,9272 + 16,199 1,046)
Qdno = 60155,161 (Kj/h)
Nhit lng cn t nng dung dch xc tc:
Qnx = 40.(3,541 1,67+ 41,313 2,093 +14,164 4,175)
Qdnx= 6060,65 (Kj/h).
Vy nhit lng cn t nng nguyn liu u l:
Qn = Qna + Qno + Qnx
Qdn = 309054,768 (Kj/h).II.2.3.Nhit lng do axetaldehyt hi lu mang vo
Gi s rng CH3CHO th hi c ngng t v hi lu hon ton tr li thit b oxy ho ti nhit 200C ta c :
Lng nhit do CH3CHO hi lu mang vo:
Qhl =20 1,38 21,685 =598,506 (Kj/h).
II.2.4. Tnh lng nhit to ra t cc phn ng Lng nhit to ra t cc phn ng c tnh theo cng thc sau:
Qi = ni Hi (Kg/h).
Trong :
Hi: hiu ng nhit ca phn ng th i, Kj/mol.
Tra s tay ho l ta c bng nhit chy cc cht
Cht(Hc(kcal/mol)(Hc(kj/mol)
CH3CHO-285-1193,01
HCOOH- 64,5-269,997
CH3COOCH3- 430,9-1804,1
CH3COOH-208,3-844,941
CH3CH(OCOCH3)2-506,912-2122,34
i vi phn ng (1):
CH3CHO + 1/2 O2 ( CH3COOH , (H1
(1)
(H1 = -1193,01 -(-844,941) = - 348,069 kj/mol
Vy nhit to ra t phn ng (1) khi to thnh 5795,456 kg/h CH3COOH l:
(Kj/h).
i vi phn ng (2): 2CH3CHO + 3/2O2 ( CH3COOCH3 + H2O + CO2, (H2 (2)
((H2 = 2.(-1193,01 (-1804,1) = -581,92kJ/mol.
Vy nhit to ra t phn ng (2) khi to thnh 18,234 kg/h CH3COOCH3 l:
(Kj/h).
i vi phn ng (3): 3CH3CHO + O2 ( CH3CH(OCOCH3)2 + H2O , (H3 (3)
( (H3 = 3.(-1193,01) - (-2122,34) = -1456,69 kJ/mol.
Vy nhit to ra t phn ng (3) khi to thnh 16,789 kg/h CH3CH(OCOCH3)2 l :
(Kj/h).
i vi phn ng (4): CH3CHO + 2O2 ( HCOOH + H2O + CO2 , (H4 (4)
( (H4 ( Kj / mol ).
Vy nhit to ra khi to thnh 3,401 kg/h HCOOH l:
(Kj/h).
i vi phn ng (5 ): CH3CHO + 5O2 ( 4CO2 + 4H2O , (H5 (5)
((H5 = - 1193,01 (Kj/mol) .
Vy nhit to ra khi 3,253 kg/h CH3CHO tham gia phn ng(5) l:
=
(Kj/h).
Vy tng lng do cc phn ng sinh ra l:
Qp = Q1 + Q2 + Q3 + Q4 + Q5
Qp = 34090753,28 (Kj/h)
II.2.5.Tnh lng nhit do sn phm mang ra:
Sn phm ra khi thit b oxy ho c nhit 70oC v v bao gm c phn hi v lng.
+ Ti 70oC, tra bng ta c:
Nhit dung ring ca cc cu t 700C + Trong dung dch:
Cu t ( trong dung dch )Cp ( Kj/ Kg.)
CH3COOH2,262
CH3COOCH31,96
HCOOH1,825
Paraldehyt2,043
Nc4,19
CH3CHOd1,38
( CH3COO)2Mn1,67
+ Trong pha hi:
Cu t ( Trong pha hi )Cp (KJ/Kg.)
CH3CHO1,24
O20,930
N21,046
CO20,907
Nhit dung ring ca CH3CH(OCOCH3)2
146.C = 6.11700 + 10.18000 + 4.25100 =350600
( C = 2,401 kJ/kg.
Nhit do phn lng mang ra l:
Qlng =70.(2,262.5847,687 +1,9618,234 +1,8253,401 +2,40116,789
+ 2,043 8,735 +4,19 35,58 +1,38 21,685 + 1,67 3,541)
Qlng = 945874,190 (Kj/h).
Qhi =70.(1,2421,685 + 0,9348,272 + 1,046 16,199+ 0,907 20,601)
Qhi = 7518,813 (Kj/h).
Vy nhit do sn phm mang ra l:
Qsp = Qlng + Qhi
Qsp= 953393,003 (Kj/h).II.2.6.Tnh nhit lng tch ra khi nng nhit ca CH3CHO hi lu n nhit phn ng
Qn= 21,685 1,38.(60- 20) = 1197,012 (Kj/h).II.2.7.Tnh lng nhit tch ra bng cch lm lnh
Theo nh lut bo ton nng lng ta c:
Q0 + Qt nng + QPhn ng + QHi lu = QSn phm + QLm lnh + Qn + Qm
Q0 + Qt nng + QPhn ng + QHi lu = 34554732,34 (Kj/h).gi thit lng nhit mt mt ra mi trng Qm bng 5% tng lng nhit mang vo thit b :
Thay s ta c:
Qm=0,05 34554732,34 =1727736,617 (Kj/h).Vy QLm lnh =34554732,34 (953393,003 +1197,012 +1727736,617 )
QLm lnh = 31872405,71 (Kj/h).
II.2.9.Tnh lng nc cn thit lm lnh
Theo yu cu ca cng ngh th nhit phn ng phi lun gi khong 60 - 700C nh vy nu gi thit nc lm lnh vo 200C th khi ra khi thit b c nhit khong 600C.
Ta c:
Qll = m.C.(t
(t = t2 t1 = 60 20 = 40oC
m: khi lng nc cn dng lm lnh, (kg/h).
C: Nhit dung ring ca nc, (Kj/Kg.). Cnc = 4,181 (kJ/kg.oC )
31872405,71 = m.4,181.40
( m = 190578,843 (kg/h).
hay th tch nc cn s dng trong 1 gi l:
V = = 190,961 (m3/h).
Bng cn bng nhit lng
Lng nhit voKj/ hLng nhit raKj/h
-Do nguyn liu mang vo (Q0)154325,784-Nhit do sn phm mang ra (Qsp)953393,003
t nng nguyn liu n nhit phn ng (Qn)309054,768- Nhit do lm lnh (Qll)31872405,71
-Nhit to ra khi phn ng (Qp)34090753,28Nhit mt mt ra mi trng xung quanh (Qm)1727736,617
-Nhit do dng hi lu mang vo (Qhl)598,506-Nhit tch ra khi nng nhit axetaldehyt n nhit d phn ng (Qn )1197,012
Tng 34554732,34Tng34554732,44
IIi.tnh ton cho thit b tch phn nh
III.1.Cn bng vt cht Hn hp vo thp chng luyn gm c :
Cu t Lng,kg/h
CH3COOH 5847,687
CH3CH(OCOCH3)2 16,789
CH3CHO 21,685
CH3COOCH3 18,234
HCOOH 3,401
Paradehyt 8,735
Nc 35,58
(CH3COO)2Mn 3,541
Nhim v ca thp tch phn nh l tch ht cc cu t nh khi sn phm th nh: CH3CHO, HCOOH, CH3COOCH3, nc. Gi thit y l cc cu t nh c tch trit .
+)Sn phm nh thp:
Lng CH3CHO = 21,685 kg/h
Lng nc = 35,58 kg/h
Lng HCOOH = 3,401 kg/h
Lng CH3COOCH3 = 18,234 kg/h
+)Sn phm y:
Lng CH3COOH = 5847,687 kg/h
Lng (CH3COO)2Mn = 3,541 kg/h
Lng CH3CH(OCOCH3)2 = 16,789 kg/h
Lng Paradehyt = 8,735 kg/h
Bng cn bng vt cht
Thnh phn i vo thpKg/hThnh phn ra khi thpKg/h
Sn phm nh thp
CH3COOH5847,687CH3CHO21,685
CH3CH(OCOCH3)216,789nc35,58
CH3CHO21,685HCOOH3,401
CH3COOCH318,234CH3COOCH318,234
HCOOH3,401Sn phm y
Paradehyt8,735CH3COOH5847,687
Nc35,58(CH3COO)2Mn3,54
(CH3COO)2Mn3,541CH3CH(OCOCH3)216,789
Paradehyt8,735
Tng 5955,652Tng5955,652
III.2.Cn bng nhit lng
Qvo = QraCc thng s nht
tf= 700C
tp= 400C
tw=110 0C
Qvo = Qhl + QF + QD
Trong :
Qhl: nhit do phn hi lu mang vo
QF: nhit do hn hp u mang vo QD: nhit do hi t cung cp Qra = QW + QY + Qng + QmNhit tn tht ra mi trng xung quanh Qm=5%.QDIII.2.1.Nhit do phn hi lu mang vo
Qhl = Gi.Ci.t
Gi: lng cu t hi lu i Ci: nhit dung rin ca cu t hi lu i Nhit ca dng hi lu vo l 200C
Ti 200C c
Cu tCp, kJ/mol.
CH3COOCH31,96
CH3CHO1,38
HCOOH2,05
H2O4,18
Gi thit lng hi lu chim 10% lng sn phm nh, vy ta c:
GCHCHO = 2,169 (Kg/h)
GCHCOOCH = 1,823 (Kg/h)
GHCOOH = 0,340 (Kg/h)
GHO = 3,558 (Kg/h)
Nhit lng do dng hi lu mang vo:
Qhl = 20.(2,169 1,38 + 1,8231,96 + 0,34 2,05 +3,558 4,18)
Qhl = 442,715kJ/h
III.2.2Nhit do hn hp u mang vo QF = Qlng = 945874,190 (Kj/h)
III.2.3.Nhit do hi mang ra nh thp QY = Gi.Ci..t
Ti 400C, nhit dung ring cc cu t
Cu tCp, kJ/mol.
CH3COOCH31,96
CH3CHO2,642
HCOOH2,14
H2O4,175
Nhit lng mang ra nh thp
QY = 40.(1,9618,234+ 2,642 21,685+ 2,14 3,401+ 4,175 35,68)
QY = 9954,202 (Kj/h).
III.2.4.Nhit mang ra bi sn phm y
Nhit sn phm y l 110 0C
Cu tCp, kJ/kg.
CH3COOH2,48
CH3CH(OCOCH3)22,642
Paradehyt2,05
B qua lng xc tc ta c :
QW = 110(2,48 5847,687+ 2,642 16,789+ 2,05 8,735)
QW = 1602097,975 (Kj/h)III.2.5.Nhit do nc ngng mang ra
Gi thit nhit do nc ngng mang ra bng 20% nhit do hi t cung cp
Qng = 0,2.QD Ta c phng trnh
Qhl + QF + QD = QW + QY + Qng + Qm = QW + QY + 0,2.QD + 0,05.QD QD = [((QW + QY) (Qhl + QF)].1/0,75
QD =[(1602097,975 + 9954,202 ) (442,715+ 945874,190)].1/0,75
QD =887647,029 (Kj/h)
Vy Qng = 0,2 887647,029 = 177529,406 (Kj/h) Qm = 0,05 887647,029 = 44382,351 (Kj/h)III.2.6.Lng hi t cn dng
QD = D2.l2 = D2( r2 + C2(2) [2 197] D2: Lng hi t cn un si dung dch y thp
l2: Hm nhit ca hi t
r2: n nhit ho hi
(2: Nhit nc ngng
C2: Nhit dung ring nc ngng
r2= 2221kJ/kg
(2= 400C
C2=4,178kJ/kg.
Thay s vo ta c 2118484,985 D2 = (Kg/h).
Bng cn bng nhit lng
Lng nhit voKj/hLng nhit raKj/h
Nhit do phn hi lu mang vo442,715Nhit do hi nh mang ra9954,202
Nhit do hn hp u945874,190Nhit do sn phm y mang ra1602097,975
Nhit do hi t cung cp887647,029Nhit tn tht ra mi trng xung quanh44382,351
Nhit do nc ngng mang ra177529,406
Tng1833963,934Tng1833963,934
IV.Tnh ton cho thit b tch phn nng
IV.1.Cn bng vt cht
Hn hp i vo thp tch sn phm nng bao gm:
Cu t Lng, Kg/h
CH3COOH 5847,687
(CH3COO)2Mn 3,541
CH3CH(OCOCH3)2 16,789
Paradehyt 8,735
Hn hp c gia nhit n 1250C, ch c CH3COOH bay hi ta thu c trn nh thp Bng cn bng vt cht
Thnh phn i voKg/hThnh phn i raKg/h
CH3COOH5847,687nh thp
(CH3COO)2Mn3,541CH3COOH5847,687
CH3CH(OCOCH3)216,789y thp
Paradehyt8,735(CH3COO)2Mn3,541
CH3CH(OCOCH3)216,789
Paradehyt8,735
Tng5876,752Tng5876,752
IV.2.Cn bng nhit lng
Qvo = Qra
Qvo= QD + Qhl + QfQra = Qa + Qw + Qng + QmTrong
Qa: Nhit do axit axetic mang ra nh thp
Qw: Nhit do sn phm y mang ra
Qng: Nhit do nc ngng mang ra
Qm: Nhit mt mt ra mi trng xung quanh
QD: Nhit do hi t cung cp
Qhl: Nhit do lng hi lu mang vo
Qf : Nhit do hn hp u mang voIV.2.1.Lng nhit hi t cn cung cp
QD= (t.(Ci.mi QD = ( 5847,687 2,561 + 16,7892,642 + 8,7352,043).(125 -110)
QD = 225571,928 (Kj/h)
IV.2.2.Nhit do nc ngng em ra
Qng= 0,2 225571,928 =45114,386 (Kj/h)
IV.2.3.Nhit do hi mang ra nh
Ti t =1000C CH3COOH c Cp =2,43
( Qa =2,43 5847,687 100 = 1420987,941 (Kj/h)
IV.2.4.Nhit do hi lu mang vo
Cho lng hi lu bng 10% lng sn phm nh
Qhl = 0,11420987,941 = 142098,794 (Kj/h)
IV.2.5.Nhit mt mt ra mi trng xung quanh
Qm = 0,05.QD = 0,05.225571,928 = 11278,596 (Kj/h)
T phng trnh cn bng nhit lng
Qa + Qw + Qng + Qm = QD + Qhl + Qf ( Qw = 492387,774 (Kj/h)Bng cn bng nhit lng
Lng nhit voKj/hLng nhit raKj/h
Nhit do hi t cung cp225571,928Nhit do axetic mang ra nh1420987,941
Nhit do phn hi lu mang vo142098,794 `Nhit mang ra bi sn phm y492387,774
Nhit do hn hp u mang vo1602097,975Nhit do nc ngng mang ra45114,386
Nhit mt ra mi trng xung quanh11278,596
Tng1969768,697Tng1969768,697
V.tnh ton thit b oxy hoV.1.ng knh thit b
Gi thit chiu cao thit b l 15 m
-Lng dung dch cha trong thit b chim 80% chiu cao tong ng 12 m.
-Vn tc lng trong thit b t 0,1- 0,5m/s chn ( = 0,4 (m/s)
Lng hn hp trong thit b
V = V1 + V2 V1: Lng oxy k thut, m3/h
V2: Lng axetaldehyt k thut, m3/h
V1=[]22,4 = 1129,025 (m3/h)
V2= m/(hhTrong :
m: Lng axetaldehyt k thut
(hh: Khi lng ring
1/(hh =xi/(i xi: Phn trm khi lng cu t i
(i: Khi lng ring ca cu t i
Thay s ta c
(hh =775kg/m3 V2= 4367,306/ 775 = 5,635 (m3/h)
V = V1 + V2 = 1129,025 + 5,635 = 1134,66 (m3/h)
ng knh thit b oxy ho
D = , m
D =1,0 (m)
Qui chun D =1,0 (m)
ng knh phn trn
Dt = 1,2.1= 1,2 (m)
Chiu cao thp l 15m
Phn trn: Ht = 3m
Phn di: Hd =12mV.2.Tnh chiu dy ca thit b
Thit b thn hnh tr lm vic chu p sut trong nn chiu dy ca thit b c tnh theo cng thc:
, m [2 360]
Trong :
Dt: ng knh trong ca thit b
: H s bn ca thnh hnh tr theo phng dc
C: H s n mn b sung, bo mn v dung sai v chiu dy, m.
P: p sut trong ca thit b, N/m2 Chn vt liu ch to thit b l thp X18H10T, l thp khng g v axit axetic c tnh n mn thit b .
Thit b hn dc, hn tay bng h quang in ng vi thp X18H10T ta c:
= 0,95
p sut ca thit b
P = Ptt + Pmt
Trong :
Ptt : p sut thu tnh ca thit b, N/m2 Pmt: p sut lm vic ca thit b bng 4 atm xp x bng 4.105 N/m2 Ptt = Trong :
: Khi lng ring trung bnh ca cht lng, Kg/m3
Khi lng ring ca axetaldehyt bng 783 (kg/m3 ).
g: Gia tc trng trng, g = 9,81 m/s2
H: Chiu cao ca ct cht lng ly ti a bng chiu cao ca thp, m
H = 12 m
Suy ra: Ptt = 783.9,8112 = 92174,76 (N/m2). Vy p sut trong l :
Pt = 92174,76 + 4105 = 492174,76.105 (N/m2).
Pt 4,922105 (N/m2).
H s b sung n mn, bo mn v dung sai m v chiu dy ca thp tm
C = C1 + C2 + C3 , m
Trong :
C1: B xung do n mn xut pht t iu kin n mn ca vt liu bi mi trng v thi gian lm vic ca thit b, m.
i vi thp X18H10T vn tc g l 0,06 mm/nm thi gian lm vic t 15-20 nm. Theo ti liu ta c C1 = 1 mm
C2: B sung do dung sai bo mn C2 = 0 , do nguyn liu khng cha cc ht rn.
C3: B sung do dung sai v chiu dy, ly C3 = 0,5 mm
Vy h s b sung l: C = C1 + C2 + C3 = 1 + 0 + 0,5 = 1,5 mm
ng sut cho php ca thp X18H10T theo gii hn bn
, N/m2
Trong :
: H s hiu chnh vi loi thit b ny c = 0,9
: ng sut gii hn bn bng 550.106 (N/m2 ). nk: h s an ton bng 2,6
Vy ng sut cho php l:
(N/m2).
ng sut cho php ca thp X18H10T theo gii hn chy:
, N/m2 [2 -356]
Trong :
: h s an ton theo gii hn chy, bng 1,5
: ng sut gii hn chy bng 220.106 (N/m2). Vy ng sut cho php l:
, (N/m2).
m bo tnh bn ta ly gi tr b hn trong hai gi tr ng sut trn tnh.
Ly (N/m2).
Khi ta c:
do vy c th b qua Pt mu Vy chiu dy ca thit b l:
i vi on di thp
(m)
Ta chn S = 6 mm.
i vi on trn thp
Dt =1,2 (m)
Ta chn S = 6 mm
Kim tra ng sut thnh theo p sut th Po
P0 = P1 + Ptl Trong :
Ptl: p sut thu lc bng 1,25PtTa c: Ptl = 1,25 . 3,912.105 = 4,89.105 N/m2
P1: p sut thu tnh ca nc
P1 = g.(.H
=9,81.1000.12 = 1,18.105 N/m2
Suy ra P0 = 4,89.105+ 1,18.105 = 6,07.105 N/m2
* Cng thc kim tra ng sut:
N/m2
V tri:
N/m2
Ta thy:
= 85,5.106 N/m2 < 183,33.106 N/m2 tho mn yu cu .
V.3.Chn np v y thp
Chn y v np thit b l loi elp c g cng loi vt liu vi thn thp.
Np
Ta c ng knh thp l D = 1,2 m, da vo s liu ta c:
Chiu dy S ca np lm vic chu p sut trong c tnh theo cng thc:
(m). [2 - 385]
Trong :
hb : Chiu cao phn li ca np.
Ta chn hb = 0,25.Dt = 1,2 0,25 = 0,3 (m).
(n : H s bn ca mi hn hng tm(nu c),chn (n = 0,95.
k : H s khng th nguyn, c xc nh nh sau:
y :
d : ng knh ln nht ca l(hay ng knh ln nht ca l khng phi hnh trn), ca l khng tng cng. Chn d = 0,2 m.
N/m2 l ng sut cho php theo gii hn bn.
P : p sut trong
c P = 4,922.105 (N/m2 ),
Ta c
V :
EMBED Equation.3 Nn i lng P mu s ca cng thc tnh chiu dy S trn c th b qua.
Vy chiu dy ca np c tnh :
S
S
i lng, b sung C khi S C =2,7.10-3 m(10 mm.Do ta tng thm 2 mm so vi gi tr tnh c thn thp.
C = ( 2 + 1,5).10-3 = 3,5.10-3 mm
S = ( 3,5 + 2,7 ).10-3 = 6,2.10-3 m
Quy chun, chiu dy np thit b S = 8 mm.
Kim tra ng sut ca thnh np thit b theo p sut thu lc theo cng thc:
=117106 .
Vy chiu dy ca np thit b l S = 8 mm.
Np thit b
y
Ta c ng knh thp l D = 1 m, da vo s liu ta c:
Chiu dy S ca y lm vic chu p sut trong c tnh theo cng thc:
(m). [2 - 385]
Trong :
hb : Chiu cao phn li ca y.
Ta chn hb = 0,25.Dt = 1 0,25 = 0,25 (m).
(n : H s bn ca mi hn hng tm(nu c),chn (n = 0,95.
k : H s khng th nguyn, c xc nh nh sau:
y :
d : ng knh ln nht ca l(hay ng knh ln nht ca l khng phi hnh trn), ca l khng tng cng. Chn d = 0,2 m.
N/m2 l ng sut cho php theo gii hn bn.
P : p sut trong
c P = 4,922.105 (N/m2 ),
Ta c
V :
EMBED Equation.3 Nn i lng P mu s ca cng thc tnh chiu dy S trn c th b qua.
Vy chiu dy ca y c tnh :
S
S
i lng, b sung C khi S C =2,8.10-3 m(10 mm.Do ta tng thm 2 mm so vi gi tr tnh c thn thp.
C = ( 2 + 1,5).10-3 = 3,5.10-3 mm
S = ( 3,5 + 2,8 ).10-3 = 6,3.10-3 m
Quy chun, chiu dy y thit b S = 8 mm.
Kim tra ng sut ca thnh y thit b theo p sut thu lc theo cng thc:
.
Vy chiu dy ca y thit b l S = 8 mm.
V.4.Chn bch ni
Bch lin bng thp ni thit b
Dt(mm)D(mm)Db(mm)D0(mm)z db
Phn trn120014001325121928M20
Phn di 100012001125101528M20
V.5. Chn cc ng knh ng dn vo v ra thit b chnh ng knh ng dn nguyn liu vo chn d1 = 200 mm.
ng knh dn oxy : d2 = 150 mm.
ng knh dn Nit : d3 = 100 mm.
ng knh ng dn sn phm axit axetic : d4 = 200 mm.
ng knh dn nc vo v ra : d5 = 100 mm.
ng knh ng dn hn hp hi nh thp : d6 = 200 mm
Phn IIITnh ton kinh t
I. ngha Tnh ton kinh t l mt phn quan trng bi cho ta bit c d n c kh thi hay khng. Mt c s sn xut mun tn ti th phi t c li nhun nht nh, nht l trong iu kin kinh t th trng cnh tranh khc lit. Sn phm sn xut ra phi c th trng chp nhn c v cht lng v gi c th hiu qu kinh t cho nh sn xut chnh l yu t quyt nh xem phng n thit k c c p dng vo thc t hay khng.
II. Ni dung tnh ton kinh tDy chuyn sn xut lin tc, s ngy lm vic trong mt nm l 330 ngy, mi ngy lm vic 3 ca, mi ca 8 ting.
Nng sut 5681,82 kg/gi (sn phm).
Nng sut ca mt nm l 45000 tn /nm.
II.1. Nhu cu v nguyn liu, nhin liu v nng lng.
II.1.1.Nhu cu v nguyn liu.
Ta tnh nhu cu v nguyn liu cho qu trnh.
Nguyn liu axetaldehyt cho qu trnh: 4423,469 kg/h =4,4235 tn/h.
Nguyn liu oxy cho qu trnh: 1655,685 kg/h = 1,656 tn/h
T ta tnh lng tiu hao cho mt tn sn phm nh sau:
- Lng axetaldehyt trong mt nm:
4,4235330 24 = 35034,12tn
- H s tiu hao axetaldehyt:
- Lng oxy k thut trong mt nm:
1,656330 24 = 13115,52 tn
- H s tiu hao oxy k thut:
Nhu cu v nguyn liu.
STTTn nguyn liuH s tiu haoNhu cu trong nm(tn)
1Axetaldehyt0,7935034,12
2Oxy0,2913115,52
II.1.2.Nhu cu v in nng
- in nng dng cho chy my cng ngh c tnh theo cng thc:
W = K1.K2n.ntbT
W: in nng dng trong 1 nm.
Ntb: Cng sut trung bnh ca ng c
n: S ng c.
Ti: thi gian s dng trong mt nm (h).
K1: H s ph ti, thng ly bng 0,75.
K2: H s tn tht, thng ly bng 1,05.
Nh my s dng khong 5 ng c cng sut 8,6 kW
W = K1.K2n.ntbT
= 0,751,055 8,633024 = 268191 Kw.h
in nng dng thp sng cho phn xng ca 2 ca chiu v ti (16/24h) c tnh theo cng thc:
Ws = ni P .Ti (kw.h)
Ws: in nng dng trong mt nm (kw.h).
ni: S bng n loi i
P: Cng sut n loi i (W)
Ti: Thi gian s dng trong nm (h)
Nhu cu in thp sng.
STTTn cng trnhLoi bng (W)S lng (ci)Thi gian s dng(h)Nhu cu in trong nm (kW.h)
1Nh sn xut chnh22050528058080
2Nh sn xut ph22020528023232
3Nh bo v100552802640
4Khu cp nguyn liu22010528011616
5Khu x l nc thi220552805808
6Nh xe100552802640
7Gara t1001052805280
8Nh kho200552805280
9Khu v sinh100552802640
10Tng cng117216
Lng in tiu th trong c nm ca phn xng.
268191 + 117216= 385407 kw.h
H s tiu hao in:
Nhu cu v xc tc trong mt nm:
3,62324330 =28694,16kgII.1.3.Tnh chi ph nguyn vt liu v nng lng:
Chi ph nguyn vt liu v nng lng.
STTTn nguyn liu, nng lngn vLng dng trong nmn gi
()Thnh tin
()
1AxetaldehytTn35034,1267.1062347286,04.106
2Oxy k thutTn13115,520,08.1061049,24.106
3inKw.h3854071300501,03.106
Tng cng2348836,31.106
II.2. Tnh vn u t c nh.
II.2.1. Vn u t xy dng: Vxdn gi xy dng nh b tng ct thp ton khi c bao che l 1,82triu/m2.
Tng din tch xy dng: 3000 m2.
Vxd = 3000x 1,82.106 = 5460.106 (ng).
II.2.2. Vn u t cho thit b, my mc: Vtb.
Chi ph cho ton b dy chuyn c chuyn giao t nc ngoi l 300000USD
Tng ng vi 4800.106
Chi ph (lp t + vn chuyn ) bng 5% gi thit b:
5%.3000000 = 15000 USD = 240.106
Tng vn u t cho thit b l:
4800.106 + 240.106 = 5040.106 ()
Tng vn u t c nh:
5040.106 + 5460.106 = 10500.106
II.3. Chi ph cho nhn cng lao ng
II.3.1.Nhu cu v lao ng.
Dy chuyn hot ng theo ch t ng ho hon ton, cng nhn c nhim v kim tra, quan st ch lm vic ca my mc thit b v cht lng sn phm iu chnh hp l. Tng s cng nhn hot ng cho mi ca khong 25 ngi
S cn b, nhn vin:
+ Gim c: 1 ngi
+ Ph gim c:1 ngi
+ Cn b k thut: 3 ngi
+ Th k vn phng : 1 ngi
+ Hnh chnh: 4 ngi
+ Bo v: 4 ngi
II.3.2. Qu lng cng nhn vin trong phn xng.
Mc lng cng nhn trc tip l 2000000 /thng.
Lng gin tip v t trng tnh theo h s.
Thng k qu lng cng nhn.STTChc vS ngiH sLng thng (/ngiLng thng ton b ()Lng c nm ()
1Gim c11,53,0.1063.10636.106
2
Ph gim c11,42,8.1062,8.10633,6.106
3Cn b k thut
31,32,6.1067,8.10693,6.106
4Cng nhn trc tip751.02,0.106150.1061800.106
5Hnh chnh41.12,2.1068,8.106105,6.106
6Th k vnphng11,02,0.1062,0.10624.106
7Bo v40,81,6.1066,4.10676,8.106
Tng cng892169,6.106
Lng bi dng ca m: 1% lng.
2169,6.106 x 0,01 = 21,696.106 (ng).
Lng bi dng c hi:1% lng.
2169,6.106 x 0,01 = 21,696.106 (ng).
Bo him x hi tr cho nhn cng 10% qu lng:
2169,6.106 x 0,015= 32,544.106 (ng).
Tng s tin lng c nm:
2169,6.106+ 21,696.106 + 21,696.106 + 32,544.106 =2245,536.106 (ng).
II.4.Tnh khu haoKhu hao nh xng ly 15 nm
5460.106 :15 = 364.106 /nm
Khu hao my mc thit b ly 10 nm
4800.106:10 = 480.106/nm
Tng chi ph khu hao ca c nm:
364.106 + 480.106 = 844.106/nm
Khu hao trn 1 n v sn phm.
844.106: 45000= 18755,56 /tn.
II.5.Tnh gi thnh sn phmChi ph qun l doanh nghip ly 5% gi thnh phn xng.
0,05 x 10500.106 = 525.106 /nm.
Chi ph bn hng ly 5% gi thnh phn xng.
0,05 x 10500.106 = 525.106 /nm.
Gi thnh sn phm
Khon mcChi ph cho 1 tn sn phm ()Chi ph cho ton
b sn lng()
Nguyn liu v nng lng2348836,31.106
Tin lng v trch theo lng48213,332169,6.106
Chi ph khu hao phn xng18755,56844.106
Chi ph QLDN v CPBH23333,341050.106
Tng cng chi ph2352399,91.106
Gi thnh sn phm ti phn xng: 52,3.106 ng/tn
Gi bn ra th trng 70.106ng/tn
II.6. Tng li nhun c nm.
LN = (70.106 52,3.106) x 45000 = 796500.106
II.7. Thi gian thu hi vn
Vn u t c nh: 10500.106 .
Vn lu ng:
+ Chi ph nguyn liu v nng lng: 2348836,31.106
+ Chi lng: 2169,6.106
+ Chi ph qun l v bn hng: 1332,16.106
Tng s vn u t l:
Vt = 2362838,07.106 .
Thi gian thu hi vn
Tth =
Vy thi gian thu hi vn u t l 3 nm
Phn ivThit k xy dng
I.c s Chn a im xy dng Vic la chn a im xy dng nh my sn xut axit axetic l ht sc quan trng, i hi ngi thit k phi tnh ton sao cho ti u ho v mi mt, t c iu ngi thit k phi thu thp, tm hiu v x l nhiu thng s ca cc ngnh khc nhau nh: a cht, giao thng, xy dng.., lin quan n k hoch pht trin kinh t ca vng cng nh ca quc gia1.V qui hoch - a im xy dng phi ph hp vi qui hoch ca a phng c cc cp c thm quyn ph duyt, c kh nng hp tc vi cc nh my khc.2.iu kin h tng k thut
-Phi m bo thun li v mt giao thng lin lc, gn ng giao thng nh ng b, ng st, ng thu
-Ph hp vi mng li thng tin, cung co in, y l cc yu t rt quan trng i vi mi n v sn xut.
3.V a hnh
Khu t c chn phi c din tch v a hnh thun li cho vic xy dng. Din tch phi b tr cc hng mc cng trnh, lp t dy chuyn cng ngh. a hnh phi bng phng gim chi ph cho vic san lp mt bng, phi cao ro trnh ngp lt trong ma ma bo.
4.V a cht - gim ti a chi ph xy dng nn mng cng trnh cn chn nn t st pha ct, t ong, i... trnh nguy c st ln, l -Trnh cc vng m khong sn, a cht khng n nh
5.V v sinh mi trng
c im ca cc nh my ho cht l thng thi ra cc cht c hi nh kh c, bi bn, khi, nc cha ho cht gy nhim mi trng. hn ch ti a s nh hng ti mi trng, a im xy dng phi xa khu dn c th, khu di tch lch s cng nh danh lam thng cnh. Nc thi ca nh my lun l vn nan gii v vy phi c h thng thi hp l cng nh phi x l ti a cc ho cht gy nhim trc khi thi ra mi trng xung quanh, trng cy xanh gp phn xanh, sch p mi trng, tuy nhin chn la c a im va l tng va tho mn c cc yu cu v v sinh mi trng l rt kh khn, do vy cn cn nhc k lng.
6.Yu cu v xy lp cng nh vn hnh nh my
- Gn ngun cung cp vt liu xy dng, vt t xy dng gim gi thnh, chi ph u t xy dng c bn
- m bo cung ng ngun nhn lc cho qu trnh xy dng nh my cng nh vn hnh nh my sau ny
II.Thit k xy dng tng mt bng nh my
Nguyn tc thit k tng mt bng nh my theo nguyn tc phn vng.
1. Vng trc nh my B tr cc nh hnh chnh qun l, phc v sinh hot, cng ra vo, nh xe, bng tin v cy xanh lm p cnh quan. Din tch vng ny c din tch t 4 ( 20% din tch ton nh my.
2. Vng sn xut
B tr cc nh my v dy chuyn sn xut chnh ca nh my, nh cc xng sn xut chnh, sn xut ph tr ... Tu theo c im sn xut v quy m ca nh my din tch vng ny chim t 22 ( 52% din tch ca ton nh my.
L vng quan trng nht ca nh my nn khi b tr cn lu mt s im sau y:
- Khu t c u tin v iu kin a hnh cng nh v hng.
- Cc nh sn xut chnh, ph, ph tr sn xut c nhiu cng nhn nn b tr gn pha cng hoc gn pha trc giao thng chnh ca nh my v c bit u tin v hng.
- Cc nh xng trong qu trnh sn xut gy ra cc tc ng xu nh ting n ln, lng bi, nhit thi ra nhiu hoc d c s c (d chy, d n hoc r r cc ho cht bt li) nn t cui hng gi v tun th cht ch an ton v sinh cng nghip.
3. Vng cc cng trnh ph
Ni t cc nh v cng trnh cung cp nng lng bao gm cc cng trnh cung cp in, hi, nc, x l nc thi v cc cng trnh bo qun k thut khc
Vng ny c din tch 14 ( 28% din tch nh my nn khi b tr cc cng trnh trn vng ny ngi thit k cn lu mt s im sau y:
- Hn ch ti a chiu di ca h thng cung cp k thut bng cch b tr hp l gia ni cung cp v ni tiu th nng lng (khai thc ti a h thng cung cp trn khng v ngm di mt t).
-Nhng khu t khng thun li v hng giao thng c th b tr cc cng trnh ph
- Cc cng trnh c nhiu bi hoc cht thi bt li u phi ch b tr cui hng gi.
4.Vng kho tng v phc v giao thng Trn , b tr cc h thng kho, bn bi, cc cu bc d hng ho, sn ga nh my ... Tu theo c im sn xut v quy m ca nh my vng ny thng chim t 23 ( 37% din tch nh my. Khi b tr vng ny ngi thit k cn lu mt s im sau:
B tr cc cng trnh phi ph hp vi cc ni tp kt nguyn liu v sn phm ca my d dng thun tin cho vic nhp v xut hng ca nh my.
Tuy nhin, trong nhiu trng hp do c im v yu cu ca dy chuyn cng ngh h thng kho tng c th b tr gn lin trc tip vi b phn sn xut. Ngi thit k c th b tr mt phn h thng kho tng nm ngay trong khu vc sn xut.5. Cc hng mc cng trnh Bng Cc hng mc cng trnh ca nh my.
STTTn cc hng mc cng trnh S lngDixRngDin tch
1Nh sn xut chnh (2 tng)130 x 181080
2Nh sn xut ph130 x 12360
3Nh hnh chnh (2 tng)124 x 9432
4Hi trng (2 tng)124 x 9432
5Phng bo v33 x 327
6Gara t con112 x 12144
7Nh xe p ,xe my118 x 9162
8Nh n112 x 12144
9Phn xng c kh118 x 9162
10B cha nguyn liu112 x 9108
11Gara t ti 118 x 9162
12Trm in19 x 981
13Phn xng nc118 x 18324
14B cha sn phm118 x 12 216
15Phn xng x l nc thi29 x 9162
16B phn cu ho 112 x 9108
17Nh iu khin118 x 9162
18Nh thay qun ao, v sinh118 x 6108
19B nc19 x 9 81
20Trm bm19 x 9 81
21Khu t d tr140 x 20800
5336
Nh my sn xut axit axetic i t nguyn liu l axetaldehyt vi cng sut l 45000 tn/nm .
Din tch mt bng nh my l: 5336.4 = 21334(m2).
H s xy dng: 6. Gii php thit k xy dng tng mt bng nh sn xut
Nh sn xut c tn l: '' Phn xng sn xut axit axetic''. Phn xng hot ng lin tc 24/24 gi, chia lm 3 ca, mi ca khong 10 ngi lm vic
a. Kt cu nh sn xut
Kt cu chu lc
+ S dng b tng ct thp ton khi.
+ Ct b tng ct thp nh khng c cn trc kch thc tit din l
400x400mm. Mng trc b tng ct thp ton khi ti ch theo kch thc ct .
+ Dm mng t nn mng c kch thc 250x400mm, l=5950mm.
+ Dm sn b tng ct thp ton khi c kch thc dm chnh
400x600mm. Dm ph 250x400mm
- Mi che bng b tng ct thp lp ghp, c dc i =1:12
- Nn v sn chu axit v chy n.
b. Mt bng nh sn xut
Do yu cu ca dy chuyn cng ngh cc thit b c b tr gia phn xng sn xut. dy chuyn m bo sn xut mt cch lin tc thun li em b tr cc chi tit theo quy tc sau:
- Thit b phn ng c ng knh ngoi l 2512 - Khong cch giao thng b tr l 2m mi bn.
- Khong cch an ton lp t l 2m
- Khong cch giao thng gia l 3m
Chiu di nh sn xut xc nh theo kch thc thit b b tr dc nh .
Chiu di nh l 30m
- Chn li ct l 6x6 m
- Din tch nh sn xut (2 tng) l 2x(30x18) = 1080 m2 Bn trong nh sn xut c b tr dy chuyn sn xut axit axetic nng sut 45000 tn/ nm
Hu ht cc thit b c t tng 1 tr c thng cao v cha nc mm (21) l t trn tng 2. Nh c 2 tng nn nhiu thit b cao hn 12 m s c bo m chc chn hn, khng nhng th cng nhn s thao tc thun li hn .
c. Mt ct nh sn xut
Do yu cu b tr thit b nn chn nh sn xut xy dng 2 tng .
V cao nh th cn c cc im sau:
- Cn c vo thng gi chiu sng, phn xng khi sn xut c pht sinh rt nhiunhit, kh c nn i hi phi c thng gi, chiu sng t nhin
- Cn c vo chiu cao thit b v yu cu vn chuyn lp rp thit b . Theo quy nh thng nht ho chn chiu cao ca tng 1 l 5,4m tng 2 l 6 m
Cn c vo chiu cao thng gi v chiu sng t nhin cho phn xng , thit k ca ra vo c kch thc l 4,2x3 v ca s c kch thc l 3x3
phn VAn ton lao ng v t ng ha Trong cc nh my cng nghip ni chung c bit l nhng nh my sn xut ho cht l thng thi cc cht c hi v d chy n gy hu qu xu, v vy trong qu trnh lao ng sn xut c rt nhiu yu t gy nh hng ti nhng ngi lao ng trc tip cng nh gin tip v mi trng xung quanh. Vi mc tiu sc kho con ngi l trn ht, an ton l bn tai nn l th m bo v thc hin tt qui trnh lao ng ta cn ch n cc qui trnh lao ng sau:I.an ton lao ng
1.Yu cu khi thit k tng mt bng nh my Mt bng nh my phi m bo thi cc cht c hi thun li, mun vy mt bng nh my phi cao, vic thi nc phi d dng, mt khc phi chng c hin tng thm.
Mt bng cn phi ch n hng gi v hng mt tri, cc b phn sn xut c bi, hi kh c, c ting n, cn t cui hng gi.
B tr hng nh theo hng mt tri nh th no m bo chng nng tt, nhng li m bo nh sng, khong cch chiu sng t nhin gia cc nh c xc nh theo cng thc:
B = ( H + h )/2 ( m )
Trong : B Khong cch gia cc nh, m
H, h Chiu cao gia cc nh cnh nhau, m
Khong cch v sinh gia cc khu ch xut v vng dn c l mt yu t quan trng. trnh gy c hi n mi trng xung quanh nh my, ngi ta phi t khong cch gia cc nh my l nht nh.
2.An ton v giao thng trong nh my
Trong khu vc ch bin, sn xut c nhiu ng nh: ng t, ng gong, ng sng, ng bin...V vy vic b tr ng i phi khoa hc, va m bo chng xy ra tai nn va m bo phng chng chy n. Theo qui nh: dc ng t phi c l ng, va h, chiu rng ng